Most athletes know that a balanced diet is a sure route to workout success. But if you’re piling up on macronutrients and still feeling “meh" each time you train, it could be a lack of vitamins and minerals kicking your workout to the curb.

As well as playing an important role in energy production, vitamins and minerals are necessary for muscle recovery and repair. A deficiency in these micronutrients can also damage immune function, bone metabolism, and body hydration. And while everyone needs their daily dose of these essential substances, athletes often need a bigger batch due to a greater loss of both through increased physical activity.

Related: What's the Best Way to Track Nutrition? 5 Tips to Level Up Your Fuel Intake

But if you’re eating well, how do you know which micronutrients you’re mainly missing out on?

It can be tricky, says Sally M. Cohen, a Boston-based registered dietician. But along with a few telltale signs — such as twitching legs, muscular cramps, and low energy — there are some common nutrient deficiencies that most athletes share.

Are You Getting Enough of These Vitamins and Nutrients?

Vitamin D

“We know vitamin D plays an important role in many physiological processes such as immune function and bone health,” says Cohen, who as a running coach also specializes in sports nutrition. “But research increasingly shows a link between vitamin D status and athletic performance, injury prevention and rehabilitation, and a general decrease in inflammation.

“Since a large proportion of athletes don't get enough sun exposure to make ample amounts of endogenous vitamin D, low or even deficient status is common.”

A recent study of collegiate indoor athletes, conducted by George Mason University, backs her up. Assessing the vitamin D status among male and female basketball players, they discovered that 65 percent were vitamin D deficient.

But, of course, the sun isn’t the only way to get more vitamin D. Cohen suggests stocking up your fridge and cabinet with vitamin D-fortified dairy or dairy alternatives, as well as fortified breakfast cereals, fatty fish, sardines, egg yolks, and mushrooms.

Electrolytes: Magnesium, Potassium, and Sodium

If you’ve ever felt restless legs at night, or twitching muscles, then you may be low in electrolytes such as magnesium, potassium, and sodium. This trio of essential minerals is vital for critical neuromuscular daily functions, as well as balancing the amount of water in your body. But it is easily lost when you get your sweat on during a workout.

Related: Magnesium Helps Tackle Stress and Muscle Cramps. Here's How.

Some studies have shown that up to 75 percent of Americans do not take the recommended dietary allowance of magnesium, while others indicate that a lack of fruit and vegetables in the average American diet is resulting in low levels of potassium intake.

Of course, fruit and veggies are the go-to foods for most Spartans. Even if your intake is already high, it won’t hurt to add an extra potassium-rich banana to your post-workout snack.

Related: Try This Insane Protein-Packed Healthy Banana Bread Recipe

Antioxidants (Vitamins C & E): Zinc, Selenium, and Manganese

Certain vitamins and minerals serve as antioxidants, the substances that protect your cells against damaging free radicals. And according to Cohen, many athletes may need to boost their body’s level of these disease-busting molecules.

“Because exercise increases the body's intake of oxygen, active individuals may have increased oxidative stress at the cellular level,” she explains. “An eating pattern rich in antioxidants — including vitamins C and E, and minerals like zinc selenium, and manganese, which interrupt the oxidative process — helps combat this cellular damage.”

Increased susceptibility to infections, brain fog, and feelings of extreme fatigue may all be signs that you need to pump up the antioxidant action in your body.

“The most effective way to incorporate most antioxidants is by eating a wide variety of plant foods,” says Cohen. “Include brightly-colored fruits and vegetables. For meat eaters, zinc and selenium are also found in animal proteins.”

Amp up your fitness and wellness routine NOW. Click here to find a Spartan race close to you!