I believe in thoroughly enjoying life and enjoying delicious foods, but I'm also passionate about maintaining a lean, muscular physique. These two pursuits can be extremely difficult to balance.

That's why I've been following an intermittent-fasting (IF) eating schedule full time for a while. You can eat the foods you want—within reason—without packing on a ton of fat. More than a decade ago, researchers from Yale University School of Medicine alongside a team at the University of Copenhagen explored fasting and fat loss, and their positive results in the lab have helped in my own pursuit of a lean physique!



Here are answers to some common questions about IF and some tips to help you get the most out of your fasting program.

What Is Intermittent Fasting?

Intermittent fasting is simply the practice of going an extended period taking in zero calories—basically drinking only plain water and either black coffee or tea. Many variations of IF exist, but my preferred method involves fasting for 16 hours, then eating during an eight-hour "feeding window." This type of IF is often called 16:8 fasting.

What are the Benefits of Intermittent Fasting?

Greater Fat Burning: Research has shown that fasting for relatively long periods may result in greater fat burning and accelerated fat loss, even when daily calorie intake remains the same. Most people find that they can have a few more of their favorite cheat foods during the feeding window and still see results

Adherence: IF is relatively easy to do, and it's a diet you don't have to discontinue—ever. You can do intermittent fasting long term with no adverse health effects. Instead, you'll see health benefits from IF.

How Does Intermitten Fasting Enhance Fat Burning?

One of the key mechanisms in fasting-induced fat loss has to do with an increase in the activity of genes that up the number of calories the body uses and the amount of fat it burns.

When you fast, your body turns on genes that encode for certain uncoupling proteins and enzymes that increase fat oxidation—meaning it turns on the body's fat-burning mechanisms. In other words, you may use more calories as a fuel source during the fasted state, which can aid your weight-loss efforts.

Does Sleeping Count As Hours Toward The Fast?

Yes. For example, if you have a protein shake right before bed, then wake up eight hours later, you're already eight hours into your fast with only eight more to reach your goal of 16.



If you have a protein shake right before bed, then wake up eight hours later, you're already eight hours into your fast with only eight more to reach your goal of 16.

How to Intermittent Fast—What Should I Eat or Drink While Fasting?

Obviously, you don't eat anything during your fasting hours—no food or shakes. Water, of course, is fine. Otherwise, opt for zero-calorie, unsweetened beverages.

Calorie-free drinks with artificial sweeteners (like flavored waters and diet soda), can be problematic. There's evidence that some artificial sweeteners cause an insulin response, which would blunt your ability to burn fat and contradict the point of being in a fasted state, but that's up for debate in the scientific community.

If you're absolutely dying for something other than water or plain coffee or tea during the last few hours, opt for a sparkling water that's very lightly flavored with something like natural lime.

Do I Need To Cram A Day's Worth Of Meals Into Eight Hours?

You want to reach the same calorie and macronutrient totals as you were before—meaning amounts of fat, carbs, and protein—provided you were already on a solid diet plan that met your goals. You don't want to undereat during your feeding window, or you'll compromise your performance in the gym and your ability to build or maintain muscle.

In theory, you eat the same number of calories and macros per day, just with a different meal schedule than a typical eat-every-few-hours plan. You can always tweak calories and macros if your physique and training goals change.

What Should I Eat First Following A Fast?

I recommend a high-protein meal over one loaded with carbs when coming off a fast. Work from the lab at Yale found that when you fast then refeed with a low-carb meal, the activity of the genes that boost calorie consumption and fat burning is further increased. However, when you refeed with a high-carb meal, the activity of many of these genes is decreased.

Can I Sip On BCAAs During My Fast?

When you're consuming branched-chain amino acids (BCAAs), you're not truly fasting.



There are 20 aminos that are used as the building blocks of protein, including the nine essential amino acids as well as the 11 nonessential aminos. If you consume just one of them, you're essentially taking in protein and are technically not fasting.

One exception is if you train in a fasted state. In that case, you can sip on aminos during your workout. The benefits of BCAAs for your workout outweigh any potential negatives.

Amino acids that aren't proteinogenic can be consumed during fasting. For example, it's OK to have beta-alanine, betaine, D-aspartic acid and—even though they're not technically amino acids—L-carnitine and creatine, especially if you're training in a fasted state.

Nutrition is only one aspect of successful weight loss. You also need a solid training plan. Pair Jim Stoppani's Shortcut to Shred program on Bodybuilding.com BodyFit Elite with intermittent fasting and get ready for serious results.

About the Author

Jim Stoppani, Ph.D. [https://www.bodybuilding.com/workout-plans/about/jim-stoppanis-six-week-shortcut-to-shred 

Jim Stoppani holds a doctorate in exercise physiology from the University of Connecticut and has been the personal nutrition and health consultant to numerous celebrity clients.



About the Author

Jim Stoppani, Ph.D.

Jim Stoppani, Ph.D.

Jim Stoppani holds a doctorate in exercise physiology from the University of Connecticut and has been the personal nutrition and health consultant to numerous celebrity clients, including...

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