This Nerd Fitness article has me curious as to whether this is just a silly fad or if there’s anything to it.
Is anything misrepresented in the article? It seems even-handed enough, but there are people in the comments section talking about it like God’s gift. One poster even claims you won’t have skin-sag from losing a ton of weight if you lose it in this fashion. :dubious:
Let’s cut through the hype and talk about the facts. Would the average person losing weight and getting into shape through interval resistance training likely benefit from this approach? Would it be more for weight loss or muscle gain? Is it pointless to even try if you’re a woman (I am)?
The thing I find most appealing about it is only having to come up with two meals instead of three. I am that damned lazy.
There are some effects on eating different types of things and different times. Not all of it falls in line with some of the conventional wisdom and a lot of the dietary advice tries to build on that. The reasoning is typically pretty bad taking the individual effect and expanding it to overall diet though.
Let’s look at a selection from the article you linked:
It sounds good but it’s really looking at a short term effect across a couple hours. In the fasted portion of the day you are pulling energy from fat. That’s not necessarily a win across the whole day or longer though. If during the entire day you are putting your total daily energy needs back into the system you have extra left over to make up for what you pulled from fat. Guess where our bodies are designed to store that extra energy? Right back into the fat that was burned during the fast portion of the day.
Sure there can be some inefficiency that burns more of that energy off (pulling the calories out and then replacing them.) There’s some inefficiency in processing more complex sources like protein and fat into accessible energy (although estimates of that that inefficiency is already worked into food labeling calorie counts.) Pulling energy from fat for part of the day (or an entire day) and then replacing it later isn’t as clear as the article suggest. A short period pf burning more fat followed by periods of rebuilding it isn’t a clear win like the article suggest. The net amount of fat across time is the right measure for those worried about changing body composition. IME it’s rare to see any of these arguments even address that. You get arguments like a period of burning fat equaling a win.
From what I’d read, the main benefit wasn’t the weight loss it was the fact that it seems to activate genes like sirt1 that can help prevent diabetes, dementia and CVD.
Could it theoretically just work better because it involves consuming fewer calories? I’m tempted to try it just so I don’t have the added burden of figuring out six meals a day or whatever. But calorie restriction would be bad if you want to gain muscle, right? How does a person gain muscle and lose fat at the same time?
You know, I’ve read so many damned books on nutrition science (though not IF), I’d say I’ve read at least twenty, from Pollan to T. Collin Campbell, and I feel like I still don’t know anything.
Insert your exercise science book recommendations here.
I think it boils down to individual tolerance/preference. For some, myself included, the conventional, eating-throughout-the-day method is much easier for me psychologically than I.F. And also, from what I’ve read, it is more like partial fasting. A common daily guideline is only eat from between 2pm and 10pm, or a personally preferable 8-hour period. It allows for more variety in foods to eat but also goes long stretches with nothing in your stomach. But for weightloss/muscle retention purposes, intermittent fasting works better for some and frequent, small meals works better for others. As beowulf mentions, it’s not the panacea it is so often described as. It’s just another way to reduce calories.
I’ve never been able to gain muscle and lose weight at the same time. If I suffer any kind of muscle damage, I develop ravenous hunger and am unable to eat below maintenance. I’ve always been that way. One time I tried to eat below maintenance through sheer willpower after doing strength training and think I developed hypoglycemia. I became very confused and irritable. Not doing that again.
At the end of the day, the shitty fact is that we evolved to avoid starving. So you can read all the books in the world, it won’t change the fact that your body doesn’t want to lsoe weight and after you lose it, it wants to gain it back. Your levels of leptin, ghrelin, T3, CCK, PYY, fatty acid synthase, GLP-1, etc. will all change to make you gain the weight back. As of 2017, medicine doesn’t know how to fix that problem. Right now, the best solution outside of surgery is eternal vigilance.
Here are books about IF that may help.
Really though, I assume its just 20 pages of useful info and 200 pages of filler.
Unless you are an absolute beginner at muscle-building, no one can simultaneously lose fat and gain muscle. The goal of such diets is muscle sparing, so your body preferentially burns as much fat as possible, while preserving as much muscle as possible.
Oh, I know all too well. That’s why I think a gradual process is best for me. Whatever weight makes sense to my body I’m okay with, and I’m not going to kill myself to force it to do anything that doesn’t feel right for it. But getting stronger is an absolute imperative, and from experience, I’ve found that muscle gain increases fat loss in the long term. At my absolute fittest I was 170 pounds and I was fine with that, I was super strong (for me), with significantly less fat, improved HR, and felt great. I got that way not through straight cardio but with HIIT and tons of strength training. I’d be happy to get back there.
[QUOTE=Ambivalid]
Unless you are an absolute beginner at muscle-building, no one can simultaneously lose fat and gain muscle.
[/QUOTE]
What does this actually mean, though, practically? Can you build muscle one day and lose fat the next? Can you build muscle one week and lose fat the next? Or do you have to alternate long periods of one with the other?
Also, what constitutes a beginner? I’m pretty weak ATM but since I started working with a personal trainer a few weeks ago I’ve seen near-daily improvements in my strength. As in, I couldn’t get through this full set on Monday, but I can by Wednesday.
If you have large amounts of adipose tissue and little muscle, then at the beginning you can both lose fat and gain muscle. But that is a short-lived window. And no, you can’t really jump back and forth (a least not in a rapid day-to-day or week-to-week timeframe) from prioritizing weight loss and gaining muscle. If you have the combination of factors that i mentioned at the beginning of this post, you can do both simultaneously while not even prioritizing muscle gain. It’ll just happen as a result of a cleaned up diet and regular exercise. But that ability quickly comes to an end and the goal expands to muscle retention as well as continued fat loss.
In the long run, yes, maintaining muscle burns more calories and thus reduces the chance of adding unwanted fat. It’s much more metabolically active than adipose tissue. That’s why the exercise component of these diets doesn’t really change at all. You always should get the exercise but the dietary aspects change as your overall physical priorities shift. As in, once you burn the level of fat that you desire, you alter your diet away from fat loss and more towards fat maintenance.
ETA: I compare this to the goals and strategies of training for a bodybuilding competition. When you are preparing for a show and need to get your fat levels down as far as possible, the only thing you change is diet, not exercise. Lifting heavy (relatively of course) is a constant, regardless of other priorities. An oft-committed mistake for bodybuilders is to alter their exercise regimes to a more high-rep scheme in anticipation of a show using the mistaken belief that it is a better muscle maintenance strategy than off-season heavy lifting. It’s not.
That’s actually a really useful insight and makes me feel better, knowing I don’t have to stress too much over how I’m exercising. I prefer the CrossFit type stuff myself, where I can see marked increases in strength. It seems mild calorie restriction makes the most sense right now as I have an ample quantity of adipose tissue, lol. My read of the responses here is that it doesn’t make much difference whether this restriction is done through IF or not.
A simple diet that isn’t even a diet, but has been proven to help people lose fat, is keeping a food diary. The burden is pretty low - making sure you log everything you eat and preferably review it occasionally. Making conscious decisions about food is included in basically every diet under the sun. Just forcing that awareness and decision making through use of a food diary, even without some guiding overall faddish diet plan, seems to be enough for some people.
The issue with trying to build new muscle, as opposed to merely retain, while losing weight was mentioned above. Since it’s part of the long term goal let me encourage a different tool than we are used to in order to measure progress towards that end goal. Measure body fat not weight. For one thing it can help avoid the daily psyching yourself out on a scale where the body composition piece is a small effect compared to the noise of hydration levels and how long it’s been since your last bowel movement. A pound of fat hold about 3,500 calories. You aren’t really tracking the small differences that a measured diet change is making day to day because the scale isn’t that precise. There’s also the issue that the scale will look like you are failing during periods where you may be building muscle. It can also make you overcount successes where you have been losing the muscle you want to keep. “I gained two pounds this month” could be a sign of a great month getting fitter. Treating it like it’s necessarily a failure, and potentially making changes to your plan based on that “failure,” can be counterproductive.
A way to do that is as simple as having your husband help you with a measuring tape to take a couple measurements and putting them into a calculator like this one. From my time in the Army I’m well aware of the debate about accuracy issues for different body types that can occur. That’s more of an issue if the number itself needs to be accurate (The Army standard was the specific body fat percentage computed. The accuracy had career implications.) Most of that inaccuracy is less relevant when you are just tracking progress. A consistent accuracy issue between measurements disappears if you are paying attention to the change in body fat content.
Yeah, I’m not really one of those people who obsess over weight. I’m honestly fine observing the basic progress of my pants getting looser. I’d rather set fitness goals, like doing a pull-up, or flipping a four hundred pound tire, than a weight goal. I might check in on my weight every month or so to make sure I’m not going the opposite direction of my goals. Sound advice.
I would say I track my food on 80% of days. If I tried IF I would be especially careful with that to ensure I’m not eating too little. Where it appeals to me is having fewer decisions to make in a given day.
A lot of people have success with intermittent fasting, but I can’t tell if it’s just another way to restrict calories like any other diet, or if the particular metabolic theories proponents use to explain it have any validity.
I think it is interesting that we (society in general) talk about all these different diets like one food or another will magically make our bodies lose fat. Nothing works that way.
I truly think that being successful at weight loss and keeping the weight off is all in finding the strategy that works for you. While the basics of weight loss (calories in-calories out) are universally true, what your brain and stomach think is filling or satisfying will be different for each person. A few year ago, Weight Watchers was toting how filling and satisfying soup was and how that would be the key to you losing weight. I was sitting here, sipping my soup, thinking about how ANYONE could possibly think soup is filling.
I’ve matured since then and, it turns out, you just gotta find the thing that works for you. Everyone is different. If you feel super satisfied eating salads every day and that helps you lose/maintain your weight, do it. If you feel better eating two meals instead of six in a day, do it. As long as you burn more calories than you bring in, you’ll lose weight.
Though I will say - The only way to know how many calories you eat is to track what you eat. I’m not always faithful though.
It’s true. I’m just trying to find the thing. 90% of my stress around food is ''What’m I gonna eat now?" It might be helpful to narrow that stress window.
That said there is something to the timing of intake during the day, at least to the increased negative impact of eating larger amounts very late in the day or close to bedtime.
But all witnessing for one method or another aside what works for one may just not work so well for another. Calorie counting as a method is one way and works for some; does not work for others. Many others find much more benefit in paying attention to the quality of the food, eating higher satiety foods and less that is highly processed such as with added sugars, not eating more unless one is actually hungry, and exercising for body composition and health impacts. Few can actually calorie count well and the listed calories are often off significantly from what the actual net energy impact is anyway (net impact of nuts for example is less than the listed calories). But the method works for some and more power to 'em.
I know of this 12 week study that achieved both significant fat loss and significant muscle mass gain in the diet + resistance exercise + casein arm - from 26 to 18% body fat with 4 kg lean mass gain and 59% mean increase in strength for chest, shoulder and legs measures. Significantly more than in the whey arm which in turn was more than diet alone. Now the amount of strength gain is consistent that this was newbie gains (only newbie gains are in that range) but 26% body fat is really just borderline obese.
That study is interesting for several reasons. The absolute weight loss over the 12 weeks was similar in all three arms, a reasonably modest 2.5kg, but the impact on body composition was very much changed in the exercise added arms. The scale had them all doing the same but clearly they performed differently. And that despite the popularity of whey shakes in the weight room, casein outperformed. 4 kg lean mass gain is pretty damn impressive to achieve while losing significant fat mass.
So starting out at least borderline obese can achieve it over a three month window. I suspect you are right and that it is harder to do after that.
Muscle mass sitting at rest, btw, really does not burn enough to really matter. It’s the using it enough to maintain it that burns the calories. And it is the exercise that for its own sake has so much benefit to health.