I was reading about sports world records and found that it's true that most records are set evening or late evening time.
Usain Bolt smashed the 100-metre sprint record at the 2009 World Championships in Athletics in Berlin in a floodlit stadium under an inky night sky.
This was no coincidence: when it comes to sporting prowess, timing matters. For activities relying on sheer muscle power and endurance, evening or late afternoon are when most world records have been set, probably due to assistance from peaks in the daily rhythms of a number of the body’s key physiological outputs. Source
But what about everyday exercisers? Is there an optimal time of day to get the most out of workouts?