Most wellness experts will tell you that you should avoid eating shortly before exercise, as this can harm your performance. The logic goes that eating just before you work out leads to a spike and drop in blood sugar, but is this really as damaging to your wellbeing as people believe? Not according to the New York Times, who recently featured an article busting this fitness dogma as a myth.
The New York Times noted that newer research shows that eating before a workout doesn’t necessarily impact your performance. One study, in particular, has shown that cyclists who drank sugary drinks prior to a workout were able to complete a strenuous 20-minute ride with no problems. In fact, other research has demonstrated that if you eat easily-digested carbohydrates before exercise, you may even be able to work out for longer. Still, even with that in mind, there remains a whole wealth of research and logic that strongly dictates you should skip eating before exercise, especially if you’re interested in maximizing your fat-burning potential.
When you exercise while fasting, it, in essences, forces your body to shed fat. This is because the fat-burning processes in your body are controlled by your sympathetic nervous system (SNS), which you activate through exercise and lack of food. When you combine the two, therefore, you maximise the efforts of cyclic AMP and AMP Kinases, which are cellular factors and catalysts that force the breakdown of fat and glycogen for energy. For example, one study found that fasting before you do aerobic activity helps you to reduce your body weight and body fat, but eating before a workout only helps you to lose weight, and not fat.
Another reason why you should exercise and fast at the same time is that this also yields acute oxidative stress, which, in turn, benefits your muscle. According to fitness expert Ori Hofmekler, acute states of oxidative stress are ‘essential for keeping your muscle machinery tuned. Technically, acute oxidative stress makes your muscle increasingly resilient to oxidative stress; it stimulates glutathione and SOD [superoxide dismutase, the first antioxidant mobilized by your cells for defence] production in your mitochondria along with increased muscular capacity to utilize energy, generate force and resist fatigue. Hence, exercise and fasting help counteract all the main determinants of muscle ageing. But there is something else about exercise and fasting. When combined, they trigger a mechanism that recycles and rejuvenates your brain and muscle tissues.’
The mechanism Hofmekler is referring to here is triggering genes and growth factors, which includes brain-derived neurotropic factor (BDNF) and muscle regulatory factors (MRFs). These factors signal your brain’s stem cells and your muscle satellite cells to convert into new neurons and new muscle cells, respectively. Why is that important? Because this means that exercising without eating beforehand may actually help you to keep your brain, neuro-motors and muscle fibres biologically young. More than this, the combined effect of both intermittent fasting and short intense exercise could help you to boost your growth hormones, raise your testosterone level, enhance your cognitive function and even prevent depression.
The best way to begin using this technique is to start by exercising before you eat breakfast. When we talk about intermittent fasting, we’re not talking about a cycle of binge eating or starvation, nor are we advising any other extreme form of dieting. Rather, what you’re after here is to time your meals to allow for regular periods of fasting. Some people prefer daily intermittent fasting, while others like to fast a couple of days a week or every other day. However, if you want to do daily intermittent fasting, the length of your fast should be targeted to 16 to 18 hours, or only eating between the hours of 11 am and 7 pm, for example. Basically, this means you can skip breakfast and make lunch your first meal of the day instead.