The Single Worst Thing You Can Do Before Exercising, Says Jillian Michaels


Many people exercise to get their mind and body to a healthy place. However, this journey to health doesn't start and stop with just your exercises for the day. In fact, there are steps you need to take before and after working out to ensure you are setting yourself up for success. And some of the things you may already do beforehand could be setting you up to fail. So what does famed exercise expert Jillian Michaels say is the worst thing you can do before exercising? Eat an entire meal right before.

"Don't eat a normal size meal within 60 minutes of exercise," Michaels said in an interview with The List. "Not only can it cause cramps while you exercise, but blood circulates to the stomach and intestines after we eat in order to transport the nutrients of our meal to relevant systems in our body. This causes a heart rate increase and blood vessel constriction in order to maintain your blood pressure."

Michaels further explained that instead of having your blood circulating to your stomach—which is what happens when you eat—you want it circulating to your muscles while working out, so it can deliver oxygen to the muscles during the workout. And even worse, "an elevated heart rate and constricted blood vessels only makes it that much harder" to get blood properly circulating to the muscles, she says.

However, this doesn't mean you should skip eating entirely before exercising. In fact, Michaels says exercising on an empty stomach could be just as bad. "If you work out on an empty stomach with no blood sugar, you are likely not getting your best workout in and intensity can be compromised," she told The List.


This advice differs from some popularized exercise routines. In fact, some people participate in fasted exercise, where you deliberately exercise before eating breakfast. This is based around the idea that people who exercise without eating burn twice the fat as those who eat breakfast before they work out—which is what one 2019 British study published in The Journal of Clinical Endocrinology & Metabolism claimed.

For her part, Michaels isn't too keen on the idea of fasted exercise. She says if you train in a fasted state and burn 200 calories in 30 minutes, 70 percent of those would be from fat and 30 percent from glycogen—meaning you "burned 140 calories from fat, and 60 from glycogen," she explained. Those ratios change if you eat and have "available blood sugar for greater energy, which gives you greater intensity," she says. "The greater your intensity, the more calories you burn after the workout is over."

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So, what is the perfect way to eat before exercising? According to Michaels, you should "eat something one to two hours before you train." And what you eat is as important as the times in which you eat. She says you want to "get a little of each macronutrient in their cleanest form if you can—clean protein, monounsaturated or polyunsaturated fats, and complex carbs" before exercising.

This means something like an apple with almond butter would be the perfect snack to eat an hour or so before working out, per Michaels. After all, "the carbs give energy," and the "fat and the protein help to sustain that energy and keep you from getting a blood sugar spike that might come from eating carbs alone." And to stay active, try these 21 Easy Ways to Get in More Exercise Every Day.