The best/only way to lose weight is diet (and I don't mean "a diet" but changing what goes into your mouth). Exercise of any variety is marginally helpful at best in isolation. It's great for all sorts of other things, but losing weight, not so much. Even the American Heart Association [1] kind of beats around the bush saying "maximum benefits" start at 5 hours per week (spread out 1h per day 5 days per week) and they go out of their way not to use the words "lose weight" but rather "less weight gain."
The adage about losing weight through "diet and exercise" is half lie. [2]
Don't get me wrong, you should exercise anyways, but don't expect to lose weight. That's on your diet.
Exercise surprisingly, to me at least, doesn't burn much calories for how much work goes into. A whole day of snowboarding can barely break 1k burned. or ~100 calories for a mile of walking.
Our food has to much calories in it i think. its to easy to eat crap or put some toppings on or have a snack and you suddenly added hundreds of calories to your day.
Yeah, it's all metabolic -- sugar metabolism specifically.
When you eat refined sugars, they go directly into your blood stream, causing your blood sugar to spike. Your body deals with this by producing Insulin. This triggers your body to remove glucose from your blood by turning it into fat (and protein, and glycogen), and store it for later. It also suppresses your body's ability to release stored fat. [3] Each time you eat sugar, you body becomes physically incapable of burning fat. The more this happens, the more your body gets used to high levels of insulin (insulin resistance) which turns into Type II and eventually metabolic syndrome. [1, 2] The vast majority of Type II cases are dietary issues.
Your body has a well-defined hierarchy of what gets consumed first: (0) alcohol (1) carbohydrates (2) fats then last (3) proteins. [4] If you want to burn fat, you can't have carbs or alcohol around in meaningful quantities. Of the energy stores, dietary carbs are the only ones you don't need to survive -- your brain and red blood cells, I believe are the only part of you that requires them to live, and the liver/kidneys can synthesize all the glucose they need. [5] The rest of your body, including muscles, can operate solely on lipid metabolism. [6] In theory, anyways.
This, though, is the science behind Atkins and other fat/protein/ketosis based diets.
Couldn’t agree more! My personal challenge for the past little while has been being observant of when I feel full. I’ve found this to be a productive perspective to engage in.
I'd agree on exercise being ineffective, or only marginally effective as a way to control weight long term. However there are surprisingly effective strategies to lose a lot a weight in a short time period(days-weeks) with low-intensity steady state.
It appears your paper advocates a combination of partial fasting with cardiovascular exercise, which I'm confident, works exactly as described :) and lines up with the research I've seen that exercising while fasted is more beneficial than when fed. [1] Though the fasting research I have done seems to indicate that protein sparing fasts aren't necessarily better than total abstention of food, and that protein lost during complete fasts is quickly regained upon re-feeding. [2] I speculate that this is connected to the huge spike in human growth hormone that occurs (hundreds of percent) during fasting. [3]
This would be an example where I'd argue the diet component (i.e. not eating) is much more important than the exercise component. Your BMR is ~2500kcal/day (10,000) and fat stores ~3500kcal, so fasting alone should account for 3 pounds of fat, and the 32 hours of exercise (low intensity, 330kcal/hr * 30hr = 10,000) the balance. This kind of math only works because you've got nothing coming in.
At this point this fact should not be news anymore. An average person cannot out work a bad diet. The saying I like is that abs are made in the kitchen, not the gym.
I think it depends on your training volume. It's interesting; I see so many sources that claim that exercise is not helpful for weight loss, but it's so different from my personal experience. I personally lost 25 pounds without decreasing calorie intake while preparing for and doing marathon training. I experimented with a vegetarian diet, but I lost little to no weight during that 2 or 3 month phase.
Admittedly, I saw no changes in weight until I hit about 20 miles per week when preparing for starting an actual training schedule. After around a 25 pound decrease, or ~30 to ~27 BMI, I think I'm closing in on my personal limit for weight loss without dietary changes or sacrificing more than I'd like to before the marathon, although I'm eating much more to sustain 40-50 miles per week.
At an estimate of 100 calories per mile [0], 20 miles per week is about 2,000 calories burned, and 50 miles per week adds up to 5,000. I find it difficult now to improve substantially without increasing calorie intake, but the weight loss just happens whenever I ignore nighttime hunger for 2 or 3 days a week during training. I ate the same amount or less without experiencing this hunger when I was heavier.
I wish I could offer some sort of source other than my anecdote. I can think of a few possible reasons why I'm not finding any data on this:
1. It's hard not to increase calorie intake while increasing exercise enough for weight loss to be noticeable. Based on my note above about only experiencing weight loss when I experienced mild hunger, it seems as though the same traditional calories in, calories out principle and the difficulties that come with that apply.
2. At the slower pace I've been running and that many who start off obese may run, it takes a lot of time to build up to the training volume necessary to experience weight loss. This may be difficult to replicate with a large enough number of individuals willing to participate in a study due to individual time constraints or job inflexibility.
3. This only works up to a certain point. I have not been successful in getting down to <25 BMI. BMI's an imperfect measure, but it aligns with my goals. I will be making dietary changes to decrease weight further, but intense exercise has been great for getting me started.
4. Not all calories are equal. I've learned a lot about nutrition since starting training and try to eat more foods that are high in iron. My diet is quite high in carbs, though, which most plans that don't require sacrificing calories do not recommend for weight loss.
5. It's possible that I've actually decreased my calorie intake without realizing it. I really doubt this. On Saturday to load up for a Sunday long run, I ate an entire small pizza, french fries, and tacos for dinner.
Does anyone else have similar experience with weight loss or have any sources that would advocate for high volume endurance exercise for weight loss?
The adage about losing weight through "diet and exercise" is half lie. [2]
Don't get me wrong, you should exercise anyways, but don't expect to lose weight. That's on your diet.
[1] https://www.heart.org/en/healthy-living/fitness/fitness-basi...
[2] https://www.vox.com/2018/1/3/16845438/exercise-weight-loss-m...