How To Stay Fit on Low Carb Diet

If you are among the many that stick to a diet that is low in carbs and you also do some workouts, you might be familiar with these symptoms: tiredness, inability to focus, soreness, or not having enough energy to muster to get through your usual cardio and lifting sessions.

There are benefits to cutting down on your carb consumption, but it also has a downside. You can lose a lot of energy.

The purpose of this article is not to argue about the pros and the cons of a low carb diet. No! I’m here to teach you how to stay fit on a low carb diet, assuming you’ve decided to cut down on carb consumption while continuing to train, build muscle, and drop body fat. Here’s how this can be done.

First, what are low carb diets?

There are variations in the guidelines for a diet that is low in carbs. Nutritionally, a diet that is low in carbs is one whose calorie contribution is below 30 percent (1, 2).

Most diets that are low in carbs consist of 50 – 150g of carbs daily, a moderate amount of protein and moderate-to-high fat intake.

However, for some athletes, a diet that is low in carbs could mean over 200g of carbs daily.


Low carbohydrate diets & fat adaptation

When you are on a low carbohydrate diet, your body’s efficiency at fueling with fat becomes better. This process is known as fat adaptation. The reduction in carb consumption causes an increase in ketone levels. Ketones are byproducts of fatty acid metabolism in your liver (3).

Ketones serve as a source of energy during a prolonged fast, where carbs are depleted, during long periods of exercise, or for type 1 diabetic patients (4, 5, 6).

Ketones can also fuel your brain (7).

The rest of the energy is a result of gluconeogenesis. In gluconeogenesis, your body metabolizes proteins and fats and then converts them to glucose (8).

How do you stay energetic and fit on a low carbohydrate diet?

You could revamp your training

A low carbohydrate diet can put you in shape by reducing your fat levels, but you may also sacrifice those great muscles of yours. Why? Because the glycogen within your liver and muscles are compromised when you reduce your carb intake. And with the depletion of glycogen stores, it becomes difficult for your muscles to the efforts required for the lifting of weights.

Subsequently, your strength decreases, followed by a drop in your training poundage and less stimulation of your muscles, resulting in muscle loss.


Also, when you go on a low carbohydrate diet, you are almost constantly in a hypocaloric state (where your food intake is lower than your calorie expenditure). In this state, your body searches for the “lost energy” that it requires to function, usually degrading proteins into amino acids, which can then be used for fuel. These factors necessitate the need to organize your resistance training so that it is heavy, intense and brief.

Brief workouts do not require as many calories as longer workouts. For those who think they’ve not done any reasonable amount of workout until they spend all morning at the gym, never forget that: there is an inverse relationship between training intensity and training volume.

You can do very intense training for a short period or a mild training for a long period, but it is almost impossible to train hard for a very long time. If you expend much energy on every workout, you may not last more than 20 – 30 minutes per session.


You may also want to go as heavy as you can and as quickly as possible into the workout after a warmup. Well, this is very important because glycogen and ATP are at their highest levels in a fresh muscle. And that’s when power generation is at its highest.

You can consider training your body this way: you should exert as much force as possible in as little time as possible. Your first goal could be maximizing the stress during your first workout.

Because this type of training is very intense, it becomes very important to warm up before injury.

Boosting your intensity levels

Let’s assume you want to make adjustments to your biceps routine to ensure that you are training at high intensity. You can follow the steps below:

  • Start with a barbell curl or any major mass-builder. Do 2 light warmups to 10 reps. Raise the poundage to a weight where you can’t exceed 8 reps even with good form. Reduce the weight by 10 percent on your second set, pounding away another 8 reps. On the final set, reduce the weight by 10 per cent and go for broke, striking another 8 reps before you are completely unable to do another rep.
  • Choose an isolation movement, for example, concentration curls. Use a dumbbell for your first heavy set during which you cannot exceed 8 reps. Reduce the weight by 10 percent for the second set and do another 8 reps. Drop another 10 per cent weight for the final set and go all out, doing as many reps as you can.
  • Complete your biceps workout with a movement that targets the muscle group is a different manner. I’ll go for the hammer curl, which focuses on the brachioradialis and brachialis. Strikeout 3 tough sets of 6 – 8 reps, and phew! Your biceps are in top form.

What other benefits does this have for athletes?

One outstanding benefit of a low carbohydrate diet is that it conditions the body to use fat as fuel (9).

For endurance athletes, studies have shown that this can enhance the preservation of glycogen stores and keep you running during endurance activities (10, 11).

With this, you won’t rely so much on carbs during an event, which is very important for athletes who find it hard to consume and digest carbs during exercise. It is also beneficial during endurance events where there is very limited access to food (12).


Research has also shown that low carbohydrate diets help with weight loss and general improvement in health (13, 14).

Loss of fat improves your fat – muscle ratio, which is of great importance for exercise performance (15, 16).

Doing exercises with depleted carb stores has become very popular as a training technique – referred to as “train low, compete high” (17).

This boosts fat utilization, enzyme activity, and mitochondrial function, which are beneficial in exercise performance and health (17).


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