1. Vitamin D (see link below for more details)
2. Magnesium (see link below for more details)
You've heard about the immune supporting benefits of vitamin C. But this essential nutrient also supports exercise endurance and recovery. A higher blood level of vitamin C Vitamin has been shown to boost fat burn, both at rest and during exercise, which can delay fatigue and lengthen workouts. And vitamin C is required to make tendons, ligaments, cartilage, and bones, so it plays an important role in healing the wear and tear exercise puts on your body. Getting the right amount means you can make the most of your sweat sessions.
How to get enough
Citrus fruits and bell peppers, especially red, are top sources, in addition to broccoli, Brussels sprouts, kiwi, strawberries, and cantaloupe. Taking in at least five servings of produce a day that includes rich sources is enough to saturate your body's tissues (meaning any more will be excreted).
But if you do opt for a supplement don't go overboard. Too much vitamin C, from high dose supplements, can have a pro-antioxidant effect, which increases exercise-induced stress. The Tolerable Upper Intake Level, or UL (essentially the maximum advised daily intake) for vitamin C it's 2,000 mg a day. While some people may be fine consuming more than this amount megadoses have linked to bloating and digestive upset, diarrhea, nausea, vomiting, heartburn, headaches, insomnia, and even kidney stones.
Cynthia Sass, MPH, RD, is Health's contributing nutrition editor. She privately counsels clients in New York, Los Angeles, and long distance. Cynthia is also the sports nutrition consultant to the New York Rangers NHL team and the New York Yankees MLB team, and is board certified as a specialist in sports dietetics.