2 EXERCISE BEFORE 8AM – OR AVOID IT ALTOGETHER

Exercising outdoors is possib lee ven in the height of summer but only fo rs ome people – and only at c ertain times of the day. “Fitter people ten dt o respon db ette r to the heat, so i f yo u ar e reasonably fit a n dh ealthy then yo uca np robably exercise with caution,” say s Mi keT ipton ,a professor of human an da pplied physiology and director of the extreme environments laboratory at th eUn iversit yofPo rtsmouth. “B ut a ny activity should be reschedule dt o ac oole rti me of the day, such as early morning or lat ee vening.” Depending on ho wh ot it is, you may nee dt o head o ut b efor e8 a mo r aft er 8pm to avoid the worst heat.

Even at r est o urb odies produce 100 watts of heat, simil ar t o a lightbul b,a nd that rises to about 1k ilowatt durin gad ecen tc ontinuous running pace. “With maximum-intensity exercise this shoo ts u p to abo ut 2 kW, the same asatw o-bar [electric] fire,” Tipton says. “Addin gh o tw eathe rc ondition st o this could mean heat exhausti on – the symptoms of which are clammy skin, excessive sweatin ga nd fast breathing – which is a real risk.”