Vitamins Before or After a Workout? (According to Science)

Vitamin A

This substance is essential for protein synthesis, testosterone production in males, supporting bone health, muscle growth, and strength, among many other health benefits.

This fat-soluble antioxidant may help prevent muscle breakdown during long, intense endurance exercises that require maintaining a high level of effort for longer (e.g., jogging, swimming, walking, long-distance running, and similar).

Vitamin C

Among ensuring a healthy immunity, preventing infections, and a range of other benefits, science claims that this vital vitamin aids in:

• Lowering cortisol levels and preventing muscle damage caused by oxidative stress (proven in individuals who ate five servings of fruits and vegetables rich in this vitamin every day); [1]
• Relieving exercise-induced respiratory symptoms (proven in athletes who took vitamin C pre-workout); [2]
• Collagen production (a structural protein key to strong and healthy muscles, tendons, bones, and skin that enables your joints to handle heavier weights while avoiding injury);
• Metabolizing carbohydrates for fuel to prevent fatigue;
• Formation of anabolic hormones.

You may safely take small doses of vitamin C every day at any time.

Vitamin B Complex

“B complex vitamins are mostly important in metabolism and also in energy processing and recovery. In general, they may help with energy levels. This, in turn helps with maximized results.”

- Dr. David Greuner

The Bs are essential for a healthy metabolism and fueling your cells so that you can use the stored energy from food to sustain high-intensity working out, weight training, or any other similar activity without getting exhausted.

For example, Vitamin B6, B1, B12, and others help the body use and store energy from protein and carbs, use folate, produce hemoglobin that carries oxygen around the body, make red blood cells, and keep the nervous system healthy.

B-complex also aids in metabolizing amino acids and protein critical for muscle repair.

These pre-workout energy boosters should be taken every morning because your body doesn’t store them.

Vitamin B12 (commonly found in animal products) gets better absorbed with a meal.

Also, vitamin C can block B12 absorption, so make sure you take them at least two hours apart.

Vitamin C and E

Exercising helps increase your insulin sensitivity and reduce insulin resistance. When your insulin sensitivity is good, your body better absorbs micronutrients and macronutrients, using them to build muscle instead of storing body fat. [7] [8]

Although antioxidant supplementation in high doses can minimize exercise-induced oxidative stress damage in deficient individuals, it’s not proven to work in well-trained athletes.

In addition, some research findings suggest that excessive post-workout supplementation with vitamins E and C can decrease insulin sensitivity and hinder health-promoting exercise results. [9] [10]

(Eating foods rich in antioxidants around or shortly after training may cause the same problem.)

For instance, a group of 40 young, healthy pre-trained men who participated in one study exercised for four weeks, five days per week (warm-up, running, cycling, circuit training, cool-down exercises).

Plus, the participants took 1000 mg/day of vitamin C (ascorbic acid) and 400 IU/day of E vitamin.

Such high antioxidant intake eliminated the beneficial effects of exercise on insulin sensitivity.

Antioxidant Supplements

Based on research evidence, a hefty dose of powerful antioxidants other than the two well-known above produces the same results - prevent the post-exercise damage caused by free radicals (reactive oxygen species) and decrease insulin sensitivity. [11]

That’s why my advice is to avoid excessive antioxidant intake (especially if you’re at high risk of diabetes), or if you’re deficient, at least take it one hour after training.