An article in the Times recently discussed a seeming fact that the exact same workout generated a very different heart rate in the morning than it did in the afternoon.
I would have thought that this had implications for the best time to do different types of workouts. Perhaps long aerobic runs in the morning and longer speed work in the afternoon? Perhaps fast times should be more likely to come in morning races for distance runs than for sprints?
Curious if anyone had either anecdotal observations or empirical evidence to share.
http://www.nytimes.com/2009/12/10/health/nutrition/10best.html