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<\/div>Your muscles, fat and other cells respond differently to exercise depending on the time of day<\/p>\n
Panoramic Images\/Alamy<\/p>\n<\/div>\n<\/figcaption><\/figure>\n<\/p>\n
Usain Bolt<\/a> smashed the 100-metre sprint record at the 2009 World Championships in Athletics in Berlin in a floodlit stadium under an inky night sky.<\/p>\n This was no coincidence: when it comes to\u00a0sporting prowess, timing matters. For activities relying on sheer muscle power and\u00a0endurance, evening or late afternoon are\u00a0when\u00a0most world records have been set, probably due to assistance from\u00a0peaks in the\u00a0daily rhythms of\u00a0a\u00a0number of the body\u2019s key physiological outputs.<\/p>\n But what about everyday exercisers? Is there\u00a0an optimal time\u00a0of day, or month, to\u00a0get\u00a0the most out of\u00a0workouts<\/a> and reduce the\u00a0risk of injury?<\/p>\n \u201cWhichever aspect of sport you look at \u2013 whether it\u2019s sports medicine or exercise response \u2013 time of day matters,\u201d says Qing-Jun Meng<\/a> at the University of Manchester, UK. Later afternoon or evening is when our body\u00a0temperature peaks, resulting in faster\u00a0metabolic reactions and nerve signal transmission compared with the early morning. Connective tissue is also more flexible in the afternoon<\/a>, while our reserves of glycogen \u2013 the biochemical energy source our muscles draw on during moderate to intense exercise<\/a> \u2013 have had time to be replenished.<\/p>\nCircadian rhythms<\/h2>\n