According to The Huffington Post, a Northwestern University study shows that sleep did have an immediate effect on exercise.

In a very impactful study at Northwestern University’s Feinberg School of Medicine, researchers investigated the bi-directional relationship between sleep and exercise. This study is fascinating because it did not just study the effects of exercise on sleep, but also the effects of sleep on exercise.

It concluded that exercise did not appear to have an immediate impact on sleep but showed that sleep did have an immediate — and significant — effect on exercise. The subjects had shorter exercise sessions after nights when they slept poorly. This relationship of poor sleep to diminished exercise was strongest among subjects whose sleep was the most challenged at the beginning of the study period.

View the full story at www.huffingtonpost.com