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Fitness and fasting: keeping on track


Fasted training has gained in popularity in recent times with the rise of the intermittent fasting diet methodology. But whether you fast for better fat loss, as backed by the science[1], for religious observance, or for any other reason, fasted training can be tough.

To ensure that you manage to keep working out while fasting without burning yourself out, here are a few simple tips.


Hit Your Calorie and Macro Goals

For effective training in general, whether the goal is fat loss or muscle gain, it’s always important to keep track of your target calories and macronutrients for the day (protein, fat, and carbohydrates).

When fasting however, it becomes especially important to take these factors into consideration. That’s because your “feeding windows” are likely to be small throughout the fasting period, which means that undereating – sometimes dramatically – can be an issue.

It’s hard to squeeze in, say, 3000 calories in a 4-hour feeding window (a typical intermittent fasting practice). If during this window you just eat as much as you feel like, you’ll likely find yourself dramatically undereating.

This is bad for your fitness goals in general – but it’s especially bad for your wellbeing during the fast. Remember that you’re not just eating to satisfy your hunger, but to fuel your body for the next fasted period.

Eat too little and you can expect to feel massively fatigued, grumpy, and unwell during your fast, and have your performance in the gym take a big hit.

Plan ahead to make sure you can meet your targets each day. Supplement with protein and meal replacement shakes if you need to.


Take a Good Multivitamin

Along with the risk of eating too little in general, there also a risk of eating too little nutritious food specifically. During the feeding window of an intermittent fast, it’s common for people to take a no-frills approach to getting as many calories in as possible. E.g., a loaf of bread for carbs instead of a balance of vegetable starches.

What’s missing is the variety that should ideally be present in a healthy diet.

While trying to maintain a well-rounded diet is the ideal solution, a decent backup plan is to invest in a good multivitamin and to take it during your feeding window- boosting overall health during the fast.


Get Enough Sleep

Fasting puts your body under stress. Luckily, that stress seems to promote a variety of positive changes in the body, ranging from improved fat loss[2] to cell repair[3] and more.

Nonetheless, it’s easy to push things too far and end up weak and sick if you don’t manage your fast carefully.

One of the worst things you can do during a fast is to get too little sleep.

Sleep is known to be critical for proper immune function[4], cognitive function[5], and muscle recovery[6]. If you’re not getting plenty of sleep during your fast, you simply will not have sufficient energy, recovery, or wellbeing to keep your fitness program on track.


Shorten Your Workouts, Focus on Key Exercises

By default, the body relies on its internal glycogen and glucose stores for the majority of physical exercise. The longer the exercise goes for, the more you’ll notice the absence of glycogen.

The thing about fasted training is that it leads to rapid depletion of the body’s glycogen stores, meaning that, especially during longer, moderate-intensity workouts, you’ll simply “hit the wall” and run out of energy to keep going.

To work around this, shorten your workouts as much as possible during your fast. Under an hour is good, under 45 minutes is better. 

Stick to performing your main exercises first, which would most likely be your compounds movements that require a lot of energy, and depending on your energy levels after these exercises, strip away accessory exercises that usually supplement your training if necessary. Whilst it's good to push yourself and challenge yourself in the gym, make sure to listen to your body, and know when it's time to take a step back.








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