Whether it’s a 2-mile morning jog around the neighborhood, a training run for a local 10K or an intense series of sprints in a track event, warm weather means more fitness-conscious folks are lacing up their shoes and hitting the road.But what many runners don’t realize is that they’re running on empty when it comes to the right balance of nutrients for attaining peak performance. Sports nutritionists often first recommend balanced, whole-foods meals to ensure their clients are getting the essential vitamins, minerals and amino acids needed for athletic performance; but more often than not, runners aren’t eating enough food-or the right foods-to meet their daily nutrient needs. That’s why supplements can be the saving grace for refueling the runner’s stride, bringing faster speeds, enhanced endurance and amplified energy.

Studies show that runners in particular come up short on B vitamins, zinc, magnesium and antioxidants. The type of running, whether for fitness or competition, can also determine specific nutritional gaps. For instance, recreational runners-like joggers or those who might participate in an occasional 5K race-might not deplete the same amounts of minerals, electrolytes and antioxidants that a competitive racer would.

Sports nutritionists agree that long-distance runners in particular benefit from glutamine, an amino acid that meets increased protein needs to speed muscle recovery following an event; pyruvate, a metabolism constituent that improves muscular endurance; and glucosamine sulfate to relieve joint pain and inflammation. Antioxidants are also very important to endurance runners.

Women runners in particular need to be sure to get enough iron. Because many women don’t eat enough foods high in iron, a slow-release iron supplement can keep up energy and ward off the possibility of anemia.

For sprinters, studies have shown that creatine can help. According to manufacturers’ labels, loading up on the supplement for several days can boost muscle strength and sprint performance. The trick with creatine is taking the right amount over a certain period of time to get the best benefits