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Hey everyone, and welcome to the 1L2L Blog write up for episode 3 (HIIT) and Episode 4 (IF/TRF)! Feel free to listen to the latest episode at the bottom of the page, but please subscribe on of the podcasting services above (for FREE) because the link at the bottom of the page only displays the latest episode and not previous ones.


After our last episode, the format has changed once again! 
Instead of doing an interview style podcast, I decided to go solo so I could cover more content quickly. I think in the future I’ll alternate between interviews and solo episodes. For those topics that require more in depth coverage, especially for listener mail questions that shouldn’t be relegated to a 5 minute answer.

I know it would be easy for me to take a Listener’s question and give them a simple “Yes or No” kind of answer, but I want you to know WHY I give you the answers I do, and HOW you can implement (or should not implement) these topics into your life based off not only MY subjective opinion (based on experience), but what the objective research says.

This blog post is far more detailed then my previous entries, only because it lists everything you need to know AND links to the latest research on HIIT and time-restricted eating (aka intermittent fasting) studies. Any relevant links can be found at the bottom of the page, and as I reference these research articles and related links, I’ll cite them using brackets, so check citations for further info!

This post is split into a part 1 and part 2, with the first part covering HIIT and the second part covering Intermittent Fasting (specifically a type of IF called Time-Restricted Feeding, aka TRF).
The “Research” sections go into quite a bit more detail than you probably “
need” to know, so feel free to skim read if you’d like.



The common theme of today’s discussion is the temporal (time-related) aspects of training and nutrition. 
Both High Intensity Interval Training (HIIT) and Intermittent Fasting (IF) share one thing in common: they manipulate the variable of Time
Because of people’s busy schedules nowadays, time is one of the most important reasons why people don’t train, specifically because the training and eating patterns they use don’t “match their schedule” (there are ways to change your schedule, but I’ll save that discussion for another day).
Therefore these two types of “interventions”, HIIT and IF are huge buzzwords in the fitness community. They have both been extensively researched for the last two decades, and the trickle down effect has finally occurred where we start to see the mainstream media pick it up, and does as it always does, blow things out of proportion and make it seem like HIIT and IF are miracle cures for our obesity epidemic. 
They mostly get it right though, since HIIT and IF research has been almost unanimously positive with its results. But let me assure you: HIIT and IF are just two types of training that you can add to your tool belt. As with any tool, if you sharpen it and hone your skills with it enough, it can become quite the effective weapon in the fight against obesity-related illness. 
So read on for the complete breakdown of what you need to know for HIIT and IF! And if you have any questions, please BY ALL MEANS, comment below or email me so I can address your thoughts and concerns in a follow up podcast.


What is it? Who developed it?

  • The term “High Intensity Interval training” (HIIT or HIT) is an umbrella term used in the fitness community for Tabata style workouts (which first popularized HIIT), general purpose “boot camp” style high intensity circuit training, and Sprint Interval Training (SIT).
    Some researchers [1] have tried to tease apart the terminology of HIIT (90-95% of VO2 max) and SIT (over 100% of VO2 max / supramaximal efforts.) If you’d like to read about the differences between the two, check out the paper cited below [1] for a more complete breakdown of the info, or comment below and I’ll break it down for you.

  • So HIIT, generally speaking, is when you do periods (aka intervals) of maximal (or near maximal) intense exercise followed by a somewhat short period of rest. The rest period can be a complete rest or a very low intensity “active rest” such as walking slowly after doing an all sprint.
    This is opposed to more traditional cardio called steady state cardio (referred to in the research as moderate intensity continuous training, or MICT). With steady state cardio your sole objective is to pick a certain low-to-moderate intensity and maintain that pace for the entirety of the session, without resting. Because a high intensity exercise isn’t sustainable for very long without rest intervals, this means that steady state cardio is by definition not as intense as HIIT.  
  • HIIT protocols were first brought into the limelight by Japanese researcher Izumi Tabata. I’m sure you’ve heard his name when used to describe “Tabata classes” you can take at your local gym. However most of these “Tabata” classes are way longer than Dr. Tabata’s low volume HIIT workouts, which actually can be done in under 5 minutes. Nobody pays for a 5 minute tabata, class, so more “high volume” versions were implemented, using high intensity work, but not supramaximal efforts.
  • In 1996 [2] Tabata wanted to test his new high intensity interval scheme on a group of elite speedskaters. He used a simple cycling protocol using a mechanically braked bicycle to see if there were benefits to them doing quick and intense bouts of all-out, supramaximal exercise (170% of their VO2max!), followed by minimal rest.
  • Tabata showed that doing this quick and brutal workout was just as effective at increasing their aerobic capacity (their “VO2max”, the gold standard for assessing one’s cardiovascular fitness) as a longer, 45 minute session of steady state exercise. This seminal paper opened up the floodgates for much more research throughout the next two decades, all showing the benefits of this type of cardio training, which led to many gym-goers picking it up as a staple of their routines.

How do you do it?

  • The prototypical Tabata style HIIT workout is one that uses a 2 : 1 work-to-rest ratio, so you’re working twice as long as you rest.
  • If you’re following the exact protocol Dr. Tabata used, you would pick any kind of intense (aerobically demanding) exercise that would VERY quickly tire you out. You’d perform that for 20 seconds followed by 10 seconds rest,  repeat for 6 -8 sets and that would take you about 4 minutes to complete.
  • Then, if you wanted to spice things up a bit, you could do what many in the fitness community did. You can stack this whole protocol into what I’ll refer to as a “round”. So you could repeat the entire 8 sets of HIIT for 4-5 “rounds” and boom, you’d have a 16-20 minute workout. Mix that in with a 5 minute warm up and cool down and you’ve got yourself a brutal, but effective 30 minute workout. Just note that if you do 4 -5 “rounds”, you probably won’t be able to sustain a 2 : 1 ratio, you may have to use 1 : 1 ratio.
  • Dr. Tabata personally recommends doing 6-7 sets of HIIT and you should be failing to complete the 8th and final set. Therefore if you find yourself capable of continuing on to a 9th set, you are NOT using high enough intensity.
  • The fun part is you can choose ANY high intensity exercise for the work intervals. 

For example, let’s take something very simple such as running (sprinting as hard as you can)
Here is an example of a quick 4 minute HIIT workout you could do every day:
Warm up (light jogging or brisk walking x 5 min) (Only Warm up Once)
Sprint (as fast as you can) 20 sec, Walk 10 sec.  Repeat  6-8 times.

If you get to the 8th round and you have the energy to try a 9th round, you have “failed” the workout. You may wish to consider doing a workout like the ones I list below, which are HIIT workouts that are extremely tough but they don’t require 170% of the your maximum effort, and therefore they also last longer (15 – 25 minutes)  instead of the original Tabata workout which only takes 4 -5 minutes.

Why is it popular?

  • Requires very little equipment 
  • Very low time commitment with similar results to longer steady state cardio
      • This is probably the biggest reason to do HIIT for most people.
  • Research on it has been very positive for the last 20 years
  • Since it is just a scheme that alters the variable of time, it is extremely flexible.
    Therefore it is used
    commonly in group fitness classes and boot camps
  • With the popularity and rise in boot camps and CrossFit** “boxes”, HIIT exercise has also become more popular.

    Crossfit is actually a great HIIT workout, but it slips up when it mixes in Olympic lifts, which should actually allow for more recovery than what a HIIT protocol uses. Also, some Crossfitters skip the recovery interval completely, which would not qualify as HIIT.
    It’s more of a what I like to call a SHIIT workout (Super High Intensity Interval Training..t-shirt coming soon! Check the shop 😉 ). Because if you aren’t allowing any recovery, you are jeopardizing your ability to perform the upcoming movements.  This overly fatigues you and your muscles (technically your CNS) actually limits the amount of work you. I don’t want to downplay CrossFit as all bad though, it’s a great workout. Just as long as you do it HIIT style and go easy on that Olympic lifting / skilled based stuff.

Does it work? What does the research say?

  • NOTE: Most of these studies refer to steady state cardio as MICT (moderate intensity continuous training). HIIT is reffered to by various names, but for simplicity I have ocassionally changed the naming to HIIT to avoid confusion.
  • Research says, that for CARDIOVASCULAR ADAPTATIONS, HIIT is as effective as longer duration steady state cardio.
  • Research is inconclusive with mixed results on whether or not HIIT is more effective for FAT LOSS.
  • Therefore, it in inaccurate and misleading for the mass media to be reporting HIIT as some kind of miracle weight loss method.
  • This is true for cardio in general. Remember that cardio is first and foremost, for CARDIOvascular (heart) health, so you don’t die of cardiovascular disease and other comorbidities.  Proper dieting and lifting weights to build more lean, calorie-expensive muscle should be your main strategies for losing weight specifically.  You can still use cardio to burn a few extra calories, but cardio can be a very slippery and difficult way to lose weight, especially after you’re out of the “obese” range and more in the “overweight” range, where your body will fight you every step of the way to lose weight once the initial round of fat loss has occurred.

Summaries of studies on HIIT vs MICT:

  • Weston 2014 [1] 
    This study was a meta-analysis, a type of paper that reviews the collection of dozens of original research articles and combines their results together to draw conclusions (using the pooled data sets to run a new analysis) about the topic as a whole. It’s an analysis of all other analyses, so to speak. Meta-analyses are a great starting point not only to see what the consensus is on a topic, while provide you with a roadmap to the results of the prior literature.
      • HIIT has more physiological benefits than MICT in patients with lifestyle-induced cardiometabolic disease.
        HIIT significantly improved cardiorespiratory fitness  by almost double that of steady state cardio (19.4% vs 10.3% VO2 max). This should translate into greater decreases in risks of morbidity and all-cause mortality.
      • Despite being high intensity, HIIT is well-tolerated, safe and improves the quality of life.
      • Both central  adaptations (your brain and spinal cord) and peripheral adaptations (muscular and vascular) are responsible for the superior benefits of HIIT.
  • Wewege 2017 [3]
      • There were no significant differences between HIIT and MICT for any body composition measure (aka fat loss), but HIIT required ~40% less training time commitment.

But is HIIT effective for fat loss? Technically it could be, but not any more so than regular ol’ steady state cardio. You could use either type of cardio for fat loss, but the largest factor for fat loss will ultimately be caloric restriction, not cardio.

  • Keating 2015 [4]
    The findings of Wewege (2017) were also confirmed the next year by a meta-analysis study conducted by Keating, which also concluded:
      • High-intensity interval training/sprint interval training appears to provide similar benefits to MICT for body fat reduction; however, HIIT/SIT is not a superior method for fat loss when directly compared with MICT”
  •  Alahmadi 2014 [5]
      • Although the mechanism responsible for fat and weight loss after HIIT is unclear, one possible reason is an increase in post-exercise metabolism. Excess post-exercise oxygen consumption (EPOC, also known as the “afterburn” effect) response to HIIT may have a role in increasing post-exercise fat oxidation (fat burning) through the increased levels of catecholamines (think adrenaline) generated during acute HIIT
  • Deighton (2013) [13]
      • Appetite is also suppressed with HIIT although it is not known exactly why
        These last two studies were performed on those individuals who were overweight and obese. What about people who in shape already? That brings us to our next study.
  • Billat 2001 [6]
        • Male Kenyan runners who trained at a higher intensity performed better than other elite runners who use low to moderate intensity
        • Doing high volume running with the “more is better” can lead to increased risk of lower extremity injury, so coaches can actually use HIIT to decreased risk of injury by offering HIIT training as an alternative / supplement to their normal long runs.
        • Similar findings were also found during a review of the literature by Garcia-Pinillas in 2017 [7], who concluded:
          HIIT-based running plans (2 to 3 HIIT sessions per week, combining HIIT and long runs) show athletic performance improvements in endurance runners by improving maximal oxygen uptake (VO2max) and running economy along with muscular and metabolic adaptations. To maximize the adaptations to training, both low volume HIIT and long (large volume) continuous runs must be part of training programs for endurance runners.
  • Gibala 2012 [8]
      • Found that HIIT is useful for those with managing their blood glucose issues for those with diabetes
      • Those with diabetes have insulin resistance, and they need to find ways to become more sensitive to glucose (a form of sugar our body uses universally for energy). Insulin sensitivity following exercise training may be improved by increased skeletal muscle glucose transport capacity, mediated in part by the protein GLUT4. 

GLUT 4 is a different receptor for glucose (Sugar) intake that offers an alternate route for glucose to get into your cells so it can be used for energy, and GLUT 4 is not used as much if you don’t exercise. Therefore if you are diabetic and have problems utilizing insulin, exercise can give you a new route (GLUT 4) to managing your blood sugar.

      • Skeletal muscle GLUT4 content after short-term HIT is increased by a comparable magnitude (∼2-fold) to that observed after high-volume endurance training.
      • Six sessions of HIIT over 2 weeks reduced average 24 hr blood glucose concentration. This is useful for those with Type 2 diabetes and it doesn’t require as much time commitment as steady state cardio (which is around 150 minutes per week according to established guidelines).
  • Greer 2015 [9]
    Studied men who were low-to-moderately active  during 3 isocaloric workouts. One workout they lifted weights, one they did a HIIT protocol, and the third was steady state cardio.
      • Their EPOC (excess-post oxygen consumption , aka how much extra calories they burned due to the “Afterburn effect following exercise) was higher after resistance training and after HIIT cardio when compared to steady state cardio. They also had a higher resting metabolic rate compared to steady state cardio.

Therefore for someone who is just beginning an exercise program and wants to speed up their metabolism temporarily after a workout, lifting weights and HIIT cardio is a superior way of burning calories compared to steady state cardio.

  • Hannan 2018 [10]
      • Found that “HIIT is superior to MICT (steady state cardio) in improving cardiorespiratory fitness in participants of cardiac rehabilitation. Programs of 7–12 weeks’ duration resulted in the largest improvements in cardiorespiratory fitness for patients with coronary artery disease. HIIT appears to be as safe as MICT for cardiac rehab participants.”

So not only is HIIT safe for those who have heart disease and other CVD problems, but it actually works better than steady state cardio because it improves blood flow even more so than MICT. And just FYI, both forms of cardio are way better than resting (and not working out) after a coronary event, which actually slows recovery.  Of course, any exercise program should be approved of and facilitated by your doctor, especially near the beginning of the program.

  • Kilpatrick 2014 [11]
    This is actually a great review article that is written for the lay person (it has pictures and everything ;)), except it’s not written by a team of researchers. Read the full text for free online HERE.

I don’t want to overwhelm you with every study on the subject. Just know there’s plenty more research out there to back up these claims, and you can use the studies I mentioned as a starting point for your own research if you so desire.

Interestingly, there are not currently any studies on trained individuals (men and women with resistance training experience) using a combination of resistance training (RT) and HIIT used together vs. RT + steady state cardio. This would be an interesting study, and if you hear of a study like this please comment below!  

Who is it for?

  • Anyone looking for time-saving cardio and/or variety
    Anyone can use HIIT when they are bored of steady state cardio, looking for a quicker routine, or looking to mix up their current cardio routine. Mixing up your routine can help maintain adherance to any exercise program, and helps avoid feeling burnt out.
    Remember, use it If It Fits Your Lifestyle! #IIFYL (<- I’m totally trademarking that for a t-shirt, by the way.)
  • Long-distance runners
    Believe it or not, even though this would seem to contradict the specificity principle of training (where you try to train as closely as possible to the actual motion or activity you are aiming for), research has shown [6] that even mid to long distance runners could benefit from using HIIT 1 -2 days per week in addition to their normal long distance routine. One study in particular [6] looked at elite Kenyan runners (Kenya historically has always had some of the best runners in the world) who performed HIIT training versus their peers, and they actual saw changes to their aerobic capacity, as their body was forced to deal with a new stimulus. Even novelty aside, any endurance athlete can benefit from injecting hit into their normal routines to turbo charge their cardio.
  • BodyBuilders 
    I know quite a few bodybuilders out there who LOVE lifting weights, but HATE any form of cardio. It takes too much time and it’s boring. Although I wouldn’t recommend Bodybuiders only do HIIT as their cardio (they should mix it between low intensity steady state cardio (LISS) and HIIT. It’s a big time saver and can be spaced out to avoid compromising “Leg Day”.
  • Type 2 diabetics and those with asthma
    Exercise in general helps manage blood sugar (see previous discussion of GLUT 4 receptors), but HIIT helps to do so in less time [8]. There has been some research to suggest that those partaking in a HIIT program may have better control over their asthma [12]. Next week we’ll be covered how to exercise for those with asthma, so stay tuned for more info!
  • Cardiac rehab patients 
  • As mentioned above [10], research has shown HIIT to be superior to steady state cardio for those who’ve suffered a recent stroke, TIA, heart attack etc. This high intensity approach is the complete opposite of what you might expect (the days of “bed rest” after a heart attack” are, pun intended, officially put to rest by this study.) If you don’t exercise your recovery will take longer and you may never even fully recover with just bed rest. Don’t take an inactive approach, be active!

How would YOU use it?

  • Again, as I mentioned earlier, I would use HIIT as another tool in your tool belt for getting an effective cardio workout in. I would not recommend people use HIIT workouts as some kind of “hack” to get you to lose weight faster. I would use whatever form of cardio you prefer and can stay consistent with. 
  • For example, if you LOVE steady state cardio, don’t feel like you NEED to do HIIT as a replacement. I know I use a mix of both personally. If I only have a short period of time and I want to stay focused and push myself hard in the gym, with no distractions (except maybe some pump up music), I’ll use HIIT.
    However, I also like to watch Youtube videos, TV shows, and read while I’m on my treadmill so I can multitask. I cannot do a proper HIIT workout while I multitask. I’d much rather just get in a good “flow state” where I can zone out and forget about the fact that I’m running, and let time fly by as I watch my shows or read. I actually tend to run much longer and burn more calories when I do this.
  • Just because I use steady state cardio doesn’t mean I don’t do regular interval training (interval training with only moderate intensity), where I run for a bit at moderate to high intensity with some walking breaks thrown in there. I use all 3 forms of cardio to my advantage: HIIT, steady state cardio, or interval training based off my mood and circumstance.


Note: Before every workout you should still try to warm up for 5 – 10 min of walking or jogging before you begin the HIIT workout. Keep in mind that you have some wiggle room for rest period length. If you feel nauseous, just sit down for a few minutes and relax, your body isn’t used to this yet but it will be soon. When you first start out you may only want to do 1 or 2 of these exercises, rather than the whole routine. 


Example BEGINNER (1:1) HIIT workout:

  1. Sprinting x 15 sec, walking x 30 sec 

    (yes, it’s a bit longer of a rest period than the 1:1 ratio, but trust me you’ll need it)

  2. Squatting in place x 20 sec, standing in place x 10 sec 

  3. Jumping Jacks x  20 sec, resting x 10 sec 

  4. Mountain climbers x 20 sec, weeping softly in the corner x 10 sec 


    (165 seconds per round, 990 – 1,156 sec total = 16.5- 19.25 min total)
    *Just joking! (You won’t even have TIME to cry in the corner 😉 )

    WARNING! Before attempting the advanced workout below please read this:
    I don’t care if you’re Usain Bolt or Michael Phelps, you should feel DEAD TIRED if you try to do this workout for 8 intervals. If you find yourself able to achieve full 8 intervals, you aren’t “cool” or “tough”, you just did the workout wrong. This is because every interval is an ALL OUT effort (unsustainable intensity) followed by a rest time that is intentionally too short for you to recover fully.

Example ADVANCED (2:1) HIIT workout:

  1. Sprinting x 15 sec, walking x 15 sec

    (yes, it’s a bit longer of a rest period than the 2:1 ratio, but trust me you’ll need it)

  2. Squat Jumping x 20 sec, standing in place x 10 sec 

  3. Burpees x  20 sec, faceplanting in the ground x 10 sec 

  4. Mountain climbers x 20 sec, weeping softly in the corner x 10 sec 


    (150 seconds per round, 900 – 1,050 sec total = 16.5- 17.5 min total)

    Other good exercises: Jump rope, lunge stance switches, high knees, hopping on one leg, plyo pushups, etc

TIP: Don’t sweat it if you can’t do the 2 : 1 work to rest ratio. Start out with a 1 : 1 work to rest ratio. Or just start each exercise with 15-20 seconds of exercise and then spend the rest of the minute resting. Each time you do the workout, try to decrease your rest time until you eventually get to the 2 : 1 ratio. Unless of course, you’d prefer your workout to take longer. 


Example BEGINNER (1:1) HIIT workout:

  1. Step-ups on 4 – 12″ step x 20 sec, walking towards battle ropes x 20 sec

  2. Battle Ropes x 20 sec, rest x 20 sec

  3. Agility ladder x 30 sec, rest x 30 sec

  4. Kettlebell swings (10 lbs) x 30 sec, crying in the corner x 30 sec


    (230 seconds per round, 1380 – 1610 sec total = 23.0 – 26.8 min total)

WARNING! Before attempting the advanced workout below please read this:
I don’t care if you’re Usain Bolt or Michael Phelps, you should feel DEAD TIRED if you try to do this workout for 8 intervals. If you find yourself able to achieve full 8 intervals, you aren’t “cool” or “tough”, you just did the workout wrong. This is because every interval is an ALL OUT effort (unsustainable intensity) followed by a rest time that is intentionally too short for you to recover fully.

Example ADVANCED HIIT (2:1) workout:

  1. Box jumps x 20 sec, pacing around nervously x 20 sec

  2. Battle Ropes x 30 sec, resting x 15 sec

  3. Rowing ergometer x  30 sec, walking towards kettlebell x  15 sec

  4. Kettlebell swings (1/2 body weight) x 30 sec, crying in the corner x 15 sec


    (205 seconds per round, 1230 – 1435 sec total = 20.5 – 23.9 min total)

 Other good exercises: Treadmill, Elliptical, Stairmaster, Stair climber, etc, as long as they’re available and nearby.
Again, you can choose any exercise you want (i.e. push-ups, squats, jumping jacks, etc), and you could alternate between each exercise in a circuit if you wanted. For example you could do sprinting, then jumping, then burpees, then go back to sprinting again. Be creative and have fun! HIIT can be much more interesting than a boring old steady-state workout.
Obviously the less equipment used, the easier it is to implement a HIIT workout. I’ve also personally found it challenging to do HIIT workouts on something like a commercial grade treadmill you’d find in a gym, because it takes too long to adjust between your fast and slow speeds. I personally like to use treadmills that have quick speed selection where I can switch between 3 mph walking and 10 mph running back and forth with the press of a button.
Also…why don’t treadmill manufacturers let you choose your own custom interval length? It always bothers me that you can’t set the work and rest interval length yourself. Let people customize their experience so they can do their own custom HIIT!

A.k.a. Time-Restricted Feeding (TRF)

What is it? Who developed it?

  • First of all, let’s talk about what intermittent fasting is NOT.
    Intermittent fasting (IF), also called time-restricted feeding, or TRF, the kind I will be reviewing in this article, is not a type of “diet” per se, because it does not focus on WHAT you eat. It focuses on WHEN you eat.
  • Second of all, IF is not the same thing as regular fasting, which is abstaining from eating for longer than a whole day.  And “fasting” is not the same thing as “starving”. Even continuous fasting (1 -7 days without eating) is not “starving your body”, either, as long as it is intermittent in nature. Starving is when your body is literally wasting away as it is both underfed and malnourished. Do not ever “starve” yourself by going too long without eating or overly restricting calories per day.**
  • There are also several types of IF, including alternate day fasting and time-restricted feeding, or “TRF“.
    TRF is the type I will be focusing on.
  • So what is IF/TRF?
    Time-restricted feeding (TRF) is a type of meal planning scheme where you choose a more narrow feeding window to eat than what you would normally do in the typical American diet of eating breakfast at 7, lunch at noon, dinner at 5, etc.
    Instead of eating throughout the day, you’d restrict the time you eat, typically down to a 8 hour window or less.
  • There are a lot of different ratios of fasting-to-eating that you can use. One of the most popular ratios in the fitness community is the “LeanGains” method popularized by Matrin Berkhan (and others), which is 16: 8 ratio.
    This mean you would fast for 16 hours and then eat 8 hours.
    You could also do a 20 hour fast and then only eat during a 4 hour window. This is a bit tougher, especially if you’re trying to maintain the same amount of total calories as before, but it is doable. For the sake of simplicity, I will mostly refer to the 16:8 ratio here, because it is the more popular amongst lifters (16:8, 18:6, and 20:4 are both commonly used schemes in research), although obviously you can choose any ratio you’d like when you implement it on your own.
**Another way to starve yourself would be to overly restrict your calories so low (let’s say, under 800 calories for women and 1200 calories for men) that you’re not fasting, and you eat some carbs so you never enter ketosis. They actually did this exact study back in World War II , and it is a study that would be not be approved by today’s Human Subject Review boards for ethical reasons. The men in the study ate just enough carb-containing calories to freak their bodies out, which led them to starvation and (if the study had continued any longer) eventually death. So don’t overly restrict calories. Either eat enough calories or stick to a pure fast, don’t starve yourself!


How do you do it?

  • It’s not as hard to do time-restricted feeding (TRF) as one might think. For the 16:8 and 18:6 scheme, you simply need to skip a single meal. This is typically either skipping breakfast or dinner (or eating dinner earlier while avoiding late night snacking).
  •  For example, you could break your fast (aka eat Breakfast) at noon, eat a second meal around 4 PM, and a final meal at 8 PM. That’s not hard to do.
  • At first, you may feel rumblings in your stomach in the morning as you skip your meal, but your body will adjust and you’ll find that the stomach rumbling will pass and you’ll go back to not being hungry again, and you’ll forget all about the meal you skipped.
  • If you’d like to take it a step further you could skip a second meal if you wanted to do 20:4 scheme (or just eat one small meal and one large meal within the 4 hour period). 

What if I fast longer than that? What if I ate every other day or certain days of the week?

  • You can use any ratio of fasting:feeding you’d like, however, if you go for 24 hours or more the research starts to refer to this type of intermittent fasting as “alternate day fasting”, and that is outside the scope of this article.  “Intermittent fasting” is more of an umbrella term for both time-restricted feeding and alternate day fasting
  • The type of intermittent fasting I am referring to is time-restricted feeding (TRF), and I will only review the literature available on this type of IF. Be careful if you go to search for “Intermittent Fasting” in the literature because you may get confused with the terminlogy. Stick to TRF and you’ll have better results. If you’re confused read the “Methods” section of the research paper where they explain the type of fasting scheme the used (usually also listed briefly in the Abstract).

Why is it popular?

  • It’s simple to implement and it’s FREE
    •  Dietary interventions on obese individuals have had higher compliance with TRF (more likely to stick to the program)
  • Many people report they have a suppressed appetite (and higher satiety after meals) when intermittently fasting
  • You can prevent snacking on junk food or eating an unhealthy meal just for convenience
    • You also don’t get hungry every 3-4 hours, which means meal planning (full, nutritional meals) is easier and you don’t have to be at the mercy of the clock when you don’t have access to good food (at work, traveling, etc)
  • It’s flexible. It works well with lots of diets out there such as other popular diets such ketogenic diets. Keto dieter and podcast star Joe Rogan uses a 16:8 scheme, and many fitness online influencers have begun spreading the word about TRF.

But isn't breakfast the "most important meal of the day"?

  • Breakfast is just a meal, folks. The 3 square meals a day thing is just a societal construct. There is no hard evidence that says breakfast (specifically, eating shortly after you wake up) has inherently more valued that other meals. Your body doesn’t treat each meal differently based on a clock.
  • I think a lot of old myths still linger around breakfast. Ever heard the saying “Eat breakfast like a king, lunch like a prince, and dinner like a pauper”? This phrase implies you should eat larger meals at the beginning of the day and slowly wittle down to nothing by the end of the day. It’s not exactly supported by science, yet I still see nutrition “experts” defend this type of eating, while mostly applauding it for people avoiding late night eating habits. 
  •  I remembering growing up as a kid people would make claims that you could eat as much as you want for breakfast because your body would have “all day long to burn it”**
    And technically your body does have all day long to burn it, but it never gets to completely burn your massive meal if you’re constantly feeding it with more food later. The most important thing you can track is the total amount of food you eat throughout the day, not WHEN you eat them or the size of each meal specifically.

**TANGENT TIME! if it were so simple as that, people would just binge eat their breakfast and fast the rest of their day…Oh wait that’s intermittent fasting! I guess ironically that may work after all. Nutrition is  funny thing! Sometimes you can stumble on to “genius”.

(By the way, I eat salad for brunch (my first meal) almost every day, and I love it!  There’s no such thing as “breakfast” food. You can eat a salad for breakfast and have steak and eggs for dinner, there’s no rhyme or reason for forcing yourself to eat breakfast foods like eggs, pancakes, sausage etc…These foods only exist as breakfast food in the first place because they are hyperpalatable foods that fill you up, and you can eat them even when you have no appetite. Avoid the sugary cereals, poptarts and Eggo waffles, folks. You don’t need them).

What about Bodybuilders? They eat all day and have crazy high metabolisms!

  • Ok so what about the bodybuilders who eat at LEAST 6 meals a day? They’re totally shredded, so surely the grazing thing works best for them, right?
    That’s true, most bodybuilders are eating constantly throughout the day. But this is out of practicality. They have to eat 4000 – 6000 calories in a day, and most of this is from chicken, vegetables, and rice. No cheat foods. Their protein intake alone is probably somewhere in the range of 5 – 10 chicken breasts. That is A LOT OF CHEWING. To ask someone in that position to eat all of those calories in two meals is asking a lot. It can be done, but it’s just not very convenient.
  • Speaking of convenience, this is also the reason why a lot of bodybuilders switch to liquid calories in the form of shakes. It can be hard to physically eat the right amount of calories for the day with the right macronutrient ratios, so they use protein shakes to careful control everything, which makes their job a lot easier.
  • Another reason bodybuilders eat so many meals is because they are worried about missing out on on protein synthesis (muscle building stimuli) by not spacing out their protein throughout the day. But this has also been studied in the literature, and so far the studies suggest that the act of resistance training (physically lifting weights) is a much stronger overall influencer of protein synthesis when compared to spacing out protein-rich meals. Still, a lot of bodybuilders rely on tradition and have way too much at stake for them to “risk” switching a less conventional meal timing scheme, so they stuff their face as much as possible, just in case.
  • But the bottom line is, there are bodybuilders who have been successfully using IF with their diets, and only now are they able to step out of the shadows to proclaim their success due to the popularity of IF in the lifting community.
    It may be tricky to fit so much food into only one or two meals, but it is doable.

But what about the "thermic effect of food"?

  • For those who don’t know, the thermic effect of food refers to the amount of calories it takes for your body to chemically burn up all of the food you just ate. So many people make the argument that more frequent meals would make your body constantly burn calories, which would raise your metabolism. Therefore grazing throughout the day is the best way to go. OR SO THEY SAY…
  • In reality, the “speed” of your resting metabolic rate (RMR) is unaffected by the frequency and timing of these meals. The size of the thermic effect of food is proportional to the size of the meal.
    If you eat a big meal, you get a bigger thermic effect. If you eat a small meal, you’ll get a smaller thermic effect. [2]
  • FYI in the future I will be covering the topic of “How to increase the speed of your metabolism”, but I can tell you for now, that the answer is not increasing the frequency of your meals.

Is it safe?

  • The short answer is yes, it is safe. People need not concern themselves with going into “starvation mode”, because it is not a long enough fasting period to even trigger ketosis, let alone “starvation”. Throughout history our bodies have always had to handle periods of time without food very well, and we are very well adapted to utilize fasting intervals. The hard part is training your body to “unlearn” the constant mouth pleasure we give ourselves by eating constantly throughout the day,
  • On a somewhat anecdotal note, consider how many Muslims safely practice time-restricted eating each year during Ramadan. And this type of IF is actually ever more restrictive considering that it also includes beverages.
  •  What about insulin and low blood sugar?
    Again, as long as you have a normal hormone profile your body will still maintain an even blood sugar content during fasting, as directed by powerful signaling cascades brought about mainly by insulin and cortisol.

Does it work?

  •  I’m going to defer to the research here for this one. Since diet can be influenced by so many factors (such as stress, lifestyle, genetics, cravings and cultural practices, to name a few) it is best to leave it to the results of actual studies on a population, as a starting point. You can then decide if you think it would suit you well. You may not be a “responder” to a particular diet scheme and that’s okay. Don’t give up hope though, there are lots of options out there.

What does the research say?

Note: The researcher currently leading the charge in the field of TRF is Dr. Grant Tinsley from Texas Tech University. Much of the research prior  to 2015 was done on other types of IF, such as alternate day fasting or 12 hour cycles of TRF, and they were mostly done on the general population, such as untrained men and obese untrained men, as well as one study that looked at athletes fasting at night during Ramadan. No research on your average weight lifter you might encounter in the gym, aka “resistance-trained men”. 
For completeness, I included some of these prior studies, but bear in mind the most relevant articles will be the ones by Tinsley (and his colleagues, including Moro et al) because they study the 16:8 “Leangains”-style TRF for people that actually workout.


  • Tinsley 2017 [14] 

      • Investigated whether 8 weeks of TRF would allow recreationally active men (without prior lifting experience) to begin a resistance training (RT) program while using a unique IF scheme that combined alternating days of TRF (20:4) with a more traditional diet with meals spread throughout the day.
      • They had the men eat normally for 3 days of the week (and these were the 3 days they actually trained), and then they restricted them to a 4 feeding hour window (20:4) on the other 4 days of the week. So they actually took advantage of the fact that training in a fed state allowed for better performance of RT, but they used a combination of both alternate day fasting and time-restricted eating to get the best of both worlds, in a sense. They formed an “alternate day restricted eating” scheme.
      • This study was not controlled as much because the men were allowed to eat whatever they wanted as long as it was within the 4-hour feeding window. This was likely on purpose; in real life, nobody is monitoring your eating for you, and it’s much easier to tell people to eat the same as they have been but only tweak the factor of time, ruling out the possibility that food provided by the researchers would confound the results anyways.
      • They found that, when the men were only allowed to eat whatever they wanted within such a narrow window, they ate less 650 calories each day. Despite this they did not have any meaningful changes in body composition, so they did not lose fat during the process. However, they were able to still maintain their gains in muscle size (assessed via muscle biopsy – ouch!) using this scheme. 
        Again it would appear that those who wish to restrict calories per day may find it easier to do when using a restricted eating window (TRF).
  • Moro (and Tinsley) 2016 [15]

The same year as Tinsley’s 2016 study (the former wasn’t published until 2017), Tinsley helped an Italian researcher conduct a separate study on TRF. This study finally gave us a first glance at what the wildly popular (16:8) TRF scheme would do for men with previous weightlifting experience.

      • In the first study (above), TRF did not affect total body composition nor did it have negative effects on muscle cross-sectional area after 8 weeks in young previously untrained men performing resistance training, despite the men consuming fewer calories (~650 kcal per fasting day) in the TRF group. 
        Therefore Moro’s study aimed to investigate the effects of an isocaloric TRF protocol (where subjects were not allowed to voluntarily eat less on fasting days) on body composition, athletic performance, and metabolic factors during resistance training in healthy resistance-trained  men (with 5+ yrs of lifting experience).

      •  After 8 weeks of TRF, fat mass significantly decreased in the TRF group (−16.4% vs only −2.8 % in the non-TRF group), while overall fat-free mass (muscle mass and bone density, etc) was maintained in both groups (+0.86 vs +0.64 %). 

      • Leg press maximal strength increased significantly in both groups, but no difference was present between the TRF group and the control group.
      • Anabolic hormones like total testosterone and IGF-1 (insulin-like growth factor 1) decreased significantly in TRF* after 8 weeks while no significant differences were detected in ND. This was surprising because these hormones are largely needed for muscle growth, and yet they dropped in the TRF. group. However, this decrease in hormones did not cause them to lose any muscle gains, indicating TRF may be well-suited for maintaining muscle mass (and % body fat) for the average lifter or in-season athlete.
        *It’s actually quite an ironic outcome because the researchers most likely chose not to let the participants eat fewer calories because previous literature showed that restricting calories leads to lower testosterone production. And yet, despite avoiding the calorie restriction. the TRF participants still had reduced testosterone, but with no adverse effects on their muscle “gains” or body composition.
      • Most prior IF protocols had the goal of reducing total energy intake (caloric restriction for the purpose of losing body fat in overweight and obese participants). In this study they didn’t try to restrict caloric intake, they kept the calories the same and still saw great results. So when you’re not cutting calories it’s still possible to lose fat and put on muscle, which is good news for just about anyone reading this. TRF won’t miraculously solve all your problems, but it is indeed a viable way to lift and eat freely without worrying about counting calories.
      • Blood glucose and insulin levels decreased significantly only in TRF subjects, corroborating findings from previous studies (listed below) that indicate those with insulin resistance may benefit from TRF + training schemes.  
  • Tinsley 2019 [16]

      • Compared young (18-30 yr) females with resistance training experience over an 8 week period to see if there was a difference between those who spread their meals out over a ~13 hr window vs. those in a ~ 7.5 hr window (16:8 style IF).
      • Primary finding: Both groups had muscular gains, and those following the 16:8 IF program did display impaired gains in fat free mass, skeletal muscle hypertrophy (increased muscle size), or muscular performance compared with the control group that had their feeding spread out over ∼13 h/d (all diets were similar in energy and protein intake.)
      •  The head researcher, Grant Tinsley is well known for his work in the field of body composition analysis. This study corroborates findings from other studies, which also found no statistically significant or clinically meaningful amount of fat loss from adopting a TRF/IF program.
      • However, technically if you only factor in the women who adhered strictly to the protocol (what Tinsely refers to as the PP / Per Protocol group), there WAS a significant amount of fat loss between the two TRF groups and the control group. Unfortunately in order to eliminate “bias” they had to run stats on everybody who finished the study, including those who did not strictly adhere to the TRF protocol, so there may yet be hope for TRF as a fat loss method. BUT, the more important concrete finding of this study was that TRF schemes do not prevent women from gaining muscle mass, so it is just as good as a normal diet (with more potential upsides). Future research will likely provide a more definitive verdict on fat loss utility.


  •  Sutton 2018 [17]
      •  Sutton and her colleagues recruited 8 overweight middle-aged (56 ± 9 yrs) men with pre-diabetes to partake in TRF intervention using an 18:6 ratio. This meant there was only a 6 hour feeding window, which is a bit smaller than the more popular 16:8 ratio. Interestingly, the men in the study reported it was difficult for them to eat the same amount of calories during that 6 hour window as their normal eating cycle. This challenge might not be a bad thing because it may make it easier to restrict calories for weight loss, although the researchers are considering using an 8 hr window in the future to make it easier to comply with the isocaloric conditions required.
      • Eight men might not seem like a lot of participants, but this was crossover study, where the men served as their own control. They randomly tried each intervention (with a 7 week washout period between the TRF and normal eating).
        They also provided the food and monitored everything the participants ate during the study, making this a very thorough and well-conducted study despite a smaller sample size.
      •  They found the men had improved insulin levels, insulin sensitivity, lowered blood pressure, and lowered oxidative stress levels in men with prediabetes – even though food intake was matched to the control group and no weight loss occurred. 
      • Therefore anyone who is overweight, pre-diabetic and/or with high blood pressure may benefit from TRF/IF.
      • Unfortunately, these results only apply to men, but there will likely be a follow-up study in the future for women.
  • Gasmi 2018 [18]
      • Studied old men vs young men who tried TRF (using a 12:12 scheme to see the effects of only eating during daylight hours) compared to each of their control groups to see if muscle power differed. By the way muscle “power”  is different from strength, With muscle “power” think the ability to do explosive movements rather than raw strength. Athletes rely on power especially. In addition to measuring power, they also measured body composition and they took blood samples to see if markers of inflammation differed.
      • They concluded that TRF may be effective in preventing inflammation by decreasing natural killer cells.
        As such, TRF could be a lifestyle strategy to reduce inflammation and age-related chronic diseases linked to age-related decline in immune systems, without compromising physical performance.
      • This study also showed that there was no difference in body composition or muscular power in any group (old vs. young and experimental vs control for each group).
      • One caveat to this study is that the restricted feeding window was fairly large (12 hours). The authors of the study did this to see the effects of “diurnal” (daylight hours) fasting, in contrast to a 2012 TRF Ramadan study [22] which looked at nocturnal fasting, but this makes it difficult to compare the results of these studies to the other TRF studies I mentioned, which restricted fasting to 8 or 4 hours. Perhaps under more extreme TRF protocols differences between groups may emerge.

If you also factor in the results of Tinsley 2017, which found no TRF made no difference in strength for young men, you can see that a pattern is emerging:  In all ages, TRF does not directly make you lose any extra body fat than a normal diet, but you won’t lose any of your performance during your workouts (including muscular strength and power). So TRF is just as good as traditional diets for active individuals, with little downsides. 

There have been two pilot studies done on TRF:

  •  Antoni 2018 [19] and Gabel 2018 [20]
      • Antoni concluded: TRF participants reduced total daily calories they ate, despite ad libitum (eating whatever they wanted) food access, with accompanying reductions in adiposity (fat). TRF also improved fasting glucose.
      • Gabel concluded that overweight TRF participants reduced more body weight (but not fat mass) and ate less calories relative to controls over 12 weeks. Blood pressure was also improved, but no differences were found in fat mass, lean mass, visceral fat mass, cholesterol, and fasting insulin levels.
      •  Because this was only a “pilot” study, the control group they compared their results to was from a different study (the study had similar demographics and was also overweight, but they did not participate in Gabel’s actual experiment)
      • Although these pilot studies are promising for those who are interested in using TRF for fat loss, these are not full studies and their results should be taken with a grain of salt. The purpose of a pilot study in general is to determine the feasibility of a future study. When these authors conduct their full studies in the future I will cover their results and post them here if they do in fact show similar results. 

Check out the CITATIONS section at the bottom of the page for a full list of all the referenced articles mentioned, not to mention the studies that didn’t make the cut (for the sake of brevity), such as Stote’s study 2007 [21] on men and women who use TRF without exercising, and the 2012 study on Ramadan [22] – which found that athletes maintain gains using TRF at night.

Could you mix HIIT with IF?

  • Actually this is a very popular strategy used by many in the fitness community, and it has been popularized especially by guys like Thomas DeLauer on Youtube as being the Holy Grail of fitness (combined with his ketogenic diet, of course. More on keto diets later. He tends to sensationalize results and cherry pick a bit, but it’s “mostly” harmless advice he gives).
  •  From what I could find in the research, I’ve only seen one time-restricted feeding study combined with HIIT, but it was performed on a rodent model:
  • Wilson 2018 [23]
      • Looked at HIIT + IF (alternate day fasting, not TRF) in mice and they had great results (IF attenuated fat gain, so mice were less likely to become obese)
      • If only humans had the same metabolism as a mouse. There have been plenty of exercise and dietary interventions done on mice in the past that accounted for MASSIVE amounts of weight loss for mice, but unfortunately when they try these same interventions out on humans, the results are either attenuated or absent completely. 
      • Hopefully someone can try to reproduce Wilson’s results in humans soon, so stay tuned and if there are any updates I will keep you posted here on the blog and in the podcast 😀
  • Based of the studies I mentioned, people who are diabetic or pre-diabetic would benefit from a mix of HIIT and IF, because as mentioned previously [8][15][17], both of them have a strong effect on managing blood sugar.
  • There was a great recap of the literature on animals and humans done by Bojan Kostevsky in 2012. Given the popularity of IF, He is currently rewriting a more concise version for 2019 so bookmark this webpage when he updates his website I will update this blog page as well. For now you can read the 2012 recap HERE.
  •  One final piece of advice: If you want to be optimal, I would time your HIIT workouts (and resistance training workouts) so that they are done during the feeding window of the IF/TRF cycle. This is because you have better workouts and perform better in a fed state than a fasted state. So make sure you do your workouts after breaking your fast, if you want best results. But if that does not work for your lifestyle, then by all means, do HIIT in the morning when you first get up. It is more important to get a HIIT workout in consistently by doing it in the morning if that’s what your work schedule demands.

Who is it for?

  • Those who have problems restricting calories, controlling apetite, and calorie counting
      •  Even though TRF doesn’t cause any more fat loss directly, you can still lose body fat indirectly by creating a caloric deficit (you eat less energy than you burn).  Just because there is no difference in fat loss from traditional caloric restriction, you can still create a caloric deficit and lose fat, and it’s even easier to do so when you aren’t as hungry.
      • As shown in Tinsley 2016, even when people are allowed  to eat their normal diet they tend eat less calories without having to monitor their calories closely, or count them at all, really.
  • BodyBuilders (during a “cut” phase, otherwise it would take serious dedication)
      • When a bodybuilder gets ready for a “show” they cut down on body fat to look extra lean before a competition, but often their body fights them really hard when they cut too many calories. TRF may attenuate their hunger pangs.
  • Type 2 diabetics
      • TRF increases glucose sensitivity (improving blood sugar)
  • Muslims practicing Ramadan
      • If you’re interested, there was a study looking at the effects of a Ramadan-style TRF scheme, check the citations below [22].

Who is it NOT for?

  • Anyone with joint problems (well…sort of!)
    You should not expect someone with joint problems to do high impact activities sprints, jumping, burpees, agility ladder 
  • Bodybuilders during a “bulking phase” 
  • Again, it can be done, but if you are aspiring pro bodybuilders and you’re struggling to gain weight, you may have to ditch TRF, at least until you’ve accrued some size.

When do you use it?

  • I recommend all of my clients experiment from time to time with long term diet plans (no fad diets. If you start a new program you need to stick with it for a while so your body doesn’t freak out on you because you’re sending it mixed signals). Since a lot of people come to me when their traditional diet has failed, and they’ve (purportedly) tried fixing the food contents, I give them the Intermittent Fasting talk as an approach to tweaking their TIMING, rather than content.
    However, if the content of their diet sucks, no amount of IF is going to save you.
  • Anecdotally, I can say it has worked well for me personally in the last year I have tried it. It started out as an experiment because I was curious and then I just stuck with it because it was very easy to continue.
  •  I did not start using IF for weight loss necessarily. I was pretty happy with my body composition but I was not liking my reliance on being forced to eat snacks to “hold me over” for lunch. Snacks that were processed foods with no nutritional value. 
    I would much rather just wait until lunch time when I can sit down and eat a quality meal that actually had nutrients in it.
    Therefore, I shrugged off my bias about breakfast being “necessary” and I started eating at noon. Before I knew it I wasn’t thinking twice about having salad (yes, Salad! God forbid I don’t eat cereal for breakfast) and I actually craved it.
  • I’ve also noticed that even though I’m not hungry in the morning, if I decide to eat breakfast with my girlfriend or family my appetite returns as soon as I begin to eat. And then the next day I resume by IF as if nothing ever happened. No side effects 😀

How do approach dieting in general

  • One thing you’ll learn about the way that I approach nutrition is that there are far too many people who give out dogmatic nutrition advice. As much as I would love to lay out a list of commandments as rules for you to stick to religiously, I will not do that.
    The answer in Nutrition is never Black and White, it is always IT DEPENDS. The best “diet” you can do is the one that you can easily follow and adhere to for the rest of your life. Don’t “get on a diet”, get on a LIFESTYLE CHANGE.
  •  If you find that HIIT makes it easier for you to curb your cravings and manage appetite, then use it! If you love grazing throughout the day and you have the willpower and habits to avoid the pitfalls of snacking and convenience food, then use that!
    There is no “one true diet” that will work best for everyone. You need to to experiment.
    And when you do experiment be sure to stick with diets for at least a couple months before switching to another. Your body has an amazing ability to adapt but it also loves consistency. Switching your diet between eating like crap and then doing a crazy cleanse is a surefire way to confuse your body into making mistakes with it’s hormones. Stick with it!! Avoid the yo-yo dieting. 
    There are some that are riskier than others, and then there’s the “If It Fits Your Macros” #IIFYM people, who are…clearly delusional. More on that in the future. For now, pick (and stick to) a diet that fits your lifestyle #IIFYL!


This section is reserved for when episode 3 and 4 drop. I will use this section to correct and clarify points made on the actual episode.


Next episode we will do another special episode focusing on responding to listener mail that we didn’t get to address in the first two episodes We will discuss IN DETAIL, our super fan Matt’s question what to do for those suffering with long term joint problems (exercising with chronic pain), and super fan Chaitalli’s question on exercising with asthma and “how to build exercise stamina” for beginners!

I covered a lot of topics and alluded towards future articles I would like to cover. These topics  include using Tabata for shallow water exercise, HIIRT workouts, IIFYM (dieting only for aesthetics and not health), and EPOC (afterburn effect) and resting metabolism.
If these topics interest you please write in and let me know if you’d like to know more!


Have a question or suggestion for us? Maybe you want to practice leaving us a freshly crafted feedback sandwich (visit the shop sometime in the next week to see our new Feedback Sandwich t-shirt ;))

Leave a comment below to let us know what you think. If you have a thought there are probably many other listeners who feel the same way. 
I challenge you take to the initiative now and become a part of our community by writing something below, or emailing us at!


  • When we were talking about HIIT protocols in the last episode, I mentioned High Intensity Interval Resistance Training (HIIRT), which is a novel approach being actively researched right now. It’s like a HIIT workout but with weights! Check out the seminal new paper here for free


Weston, K. S., Wisløff, U., & Coombes, J. S. (2014). High-intensity interval training in patients with lifestyle-induced cardiometabolic disease: a systematic review and meta-analysis. British Journal of Sports Medicine48(16), 1227–1234.

Belko, A. Z., & Barbieri, T. F. (1987). Effect of meal size and frequency on the thermic effect of food. Nutrition Research7(3), 237–242.

Thermic Effect of Food (TEF) response to 2 large meals, each representing 50% of daily energy needs, was compared to the TEF response to 4 small meals, each representing 25% of daily energy needs. Total 10-hour TEF, measured as increase in oxygen consumption from rest, did not differ between the large and small meal patterns (43.43 ±5.01 vs. 43.42±4.72 liters, respectively). "

Wewege, M.Berg, R.Ward, R. E., and Keech, A. ( 2017The effects of high‐intensity interval training vs. moderate‐intensity continuous training on body composition in overweight and obese adults: a systematic review and meta‐analysisObesity Reviews18635– 646. doi: 10.1111/obr.12532.

Keating, S. E.Johnson, N. A.Mielke, G. I., and Coombes, J. S. ( 2017A systematic review and meta‐analysis of interval training versus moderate‐intensity continuous training on body adiposityObesity Reviews18943– 964. doi: 10.1111/obr.12536.

Alahmadi, M. A. (2014). High-intensity Interval Training and Obesity. Journal of Novel Physiotherapies, 2014(3).

García-Pinillos, F., Soto-Hermoso, V. M., & Latorre-Román, P. A. (2017). How does high-intensity intermittent training affect recreational endurance runners? Acute and chronic adaptations: A systematic review. Journal of Sport and Health Science6(1), 54–67.

Greer B.K., Sirithienthad P., Moffatt, R.J., Marcello R.T. & Panton L.B. (2015). EPOC Comparison Between Isocaloric Bouts of Steady-State Aerobic, Intermittent Aerobic, and Resistance Training,Research Quarterly for Exercise and Sport, 86:2, 190-195, DOI: 10.1080/02701367.2014.999190

Hannan, A. L., Hing, W., Simas, V., Climstein, M., Coombes, J. S., Jayasinghe, R., … Furness, J. (2018). High-intensity interval training versus moderate-intensity continuous training within cardiac rehabilitation: a systematic review and meta-analysis. Open Access Journal of Sports Medicine9, 1–17.

Kilpatrick, M. W., Jung, M. E., & Little, J. P. (2014). HIGH-INTENSITY INTERVAL TRAINING: A Review of Physiological and Psychological Responses. ACSM’s Health & Fitness Journal18(5), 11.

Türk Y., van Huisstede A., van der Geijn GJ.Hiemstra, P., Taube, C., Braunstahl, GJ (2017). Effect of a high intensity life style program on asthma control in obese patients with asthma.

Deighton K, Barry R, Connon CE, Stensel DJ (2013) Appetite, gut hormone and energy intake responses to low volume sprint interval and traditional endurance exercise. Eur J Appl Physiol 113: 1147-1156.

Tinsley, Grant; Forsse, Jeffrey; K. Butler, Natalie; Paoli, Antonio; Bane, Annie M.; La Bounty, Paul; Morgan, Grant; Grandjean, Peter (2017). Time-restricted feeding in young men performing resistance training: A randomized controlled trial. European Journal of Sport Science. 17. 200-207. 10.1080/17461391.2016.1223173.

Moro, T., Tinsley, G. M., Bianco, A., Marcolin, G., Pacelli, Q. F., Battaglia, G., … Paoli, A. (2016). Effects of eight weeks of time-restricted feeding (16/8) on basal metabolism, maximal strength, body composition, inflammation, and cardiovascular risk factors in resistance-trained males. Journal of Translational Medicine, 14(1), 290–303.

Grant M Tinsley, M Lane Moore, Austin J Graybeal, Antonio Paoli, Youngdeok Kim, Joaquin U Gonzales, John R Harry, Trisha A VanDusseldorp, Devin N Kennedy, Megan R Cruz, Time-restricted feeding plus resistance training in active females: a randomized trial, The American Journal of Clinical Nutrition, , nqz126,

Sutton, E. F., Beyl, R., Early, K. S., Cefalu, W. T., Ravussin, E., & Peterson, C. M. (2018). Early Time-Restricted Feeding Improves Insulin Sensitivity, Blood Pressure, and Oxidative Stress Even without Weight Loss in Men with Prediabetes. Cell Metabolism, 27(6), 1212.

Gasmi 2018

Antoni 2018

Gabel, K., Hoddy, K. K., Haggerty, N., Song, J., Kroeger, C. M., Trepanowski, J. F., … Varady, K. A. (2018). Effects of 8-hour time restricted feeding on body weight and metabolic disease risk factors in obese adults: A pilot study. Nutrition and Healthy Aging, 4(4), 345–353.

Stote 2007

Chaouachi, A., Leiper, J. B., Chtourou, H., Aziz, A. R., & Chamari, K. (2012). The effects of Ramadan intermittent fasting on athletic performance: Recommendations for the maintenance of physical fitness. Journal of Sports Sciences, 30(sup1), S53–S73.doi:10.1080/02640414.2012.698297

Wilson (rat study of TRF + HIIT)


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