Prevention and Treatment of Youth Sport Injuries
an Online Resource

The most critical period for acclimatization is the first 3 to 5 days, however athletes should be acclimatized to heat gradually over a period of 7 to 14 days. For the first 5 days no more than 1 practice per day and the use of helmets and shoulder pads only is recommended. When initiating two-a-day practices common practice recommends 3 hour breaks in between sessions and nothing but rest counts as a break. This includes a regimen of days on and days off when done during the first 14 days. So if Monday consists of 2 practices in one day, Tuesday can either be one practice or a day off and Wednesday can continue as a two-day practice. Time inside alone does not constitute a break and days off do not count towards the 14 days for full acclimatization. So if an athlete is indoors in the wait room that is not sufficient as a portion of the 3 hour break and if there is no practice on Saturday or Sunday that does not count towards acclimatization because the athlete is not exposed to the elements.