Take your stride outside
Turns out you can run faster on "solar power" and get a big workout boost with the sunshine vitamin. A new British study shows vitamin D (absorbed from the sun's rays) stimulates energy-producing components of our cells, helping muscles feel stronger. Extra D also improves endurance levels, fights fatigue and speeds up recovery time. Talk about a multivitamin! The best part? If you're D-deficient, a dose from a daily supplement (1,000 to 2,000 IU a day) over a period of 10 to 12 weeks can also help your muscles work more efficiently while exercising.
Try it today: Take your workout outside, and pack your lunch with vitamin-D-rich foods like salmon, lentils and egg yolks. —Jillian Bell