Chill out: FIFA World Cup 'cooling periods' should be put on ice
This article by Dr Ric Lovell from the UWS School of Science and Health was originally published at The Conversation.
The international soccer community has been bitterly divided over the decision to award the 2022 FIFA World Cup to Qatar: beyond appalling stories of the working conditions of immigrants building stadiums to host the matches, the scheduling of the tournament during the Middle East's summer months, where temperatures often exceed 40C, is a big concern.
These issues quite rightly dominated the agenda of this month's meeting of FIFA'sexecutive committee, but hidden behind the headlines was the lesser-publicised outcome to include two "cooling breaks" during World Cup matches in Brazil next year.
Will these breaks be enough for the players to recover – and are there better options?
The premise of the "cooling periods" is to reduce the risk of players incurring heat-related illnesses (such as heat exhaustion, heatstroke, heat cramps) by enabling them to ingest fluids to alleviate dehydration and heat-strain.
The breaks, of a couple of minutes each, are to be applied by the officials (approximately 30 minutes into each half) if the match is played in conditions deemed hazardous to the player, and will be determined by a combination of the environmental temperature, solar radiation and humidity measurements.
The application of "cooling breaks" will certainly appease academics and organisations that have developed best-practice guidelines in the prevention of heat-related illnesses in sports - or those, such as the sports drinks industry, who maintain that dehydration can have a negative impact on both physical and technical aspects of soccer performance.
Yet when you view the actual figures, the incidence of heat-related illnesses (HRIs) during soccer matches is very low.
Although symptoms may be increased in hotter climates, in an audit of injuries in American collegiate fixtures, HRIs accounted for less than 1% of all injuries.
During training sessions, the prevalence was 1.7% of all injuries, which equated to 0.07 incidents per 1,000 player exposures, or one HRI in every 14,285 training sessions.
Rehydration vs time
During team sports, we often see high body temperatures and a moderate degree of dehydration, even in just mild environmental conditions.
In hotter climates, the body temperature and fluid losses increase, but only slightly, as players' physical exertions are reduced in these conditions, and the match tempo is often less vigorous.
Some academics in the area contend that the players self-regulate their efforts to ensure that they can finish the game, and leave some physical reserves for the latter stages of match-play, should they be required. Perhaps this might explain the lower prevalence of HRIs during soccer matches, even in games played in hot conditions.
Sure, playing in hot temperatures will exacerbate fluid loss, and increase the strain on the cardiovascular system. But will a two or three-minute break make any physiological difference?
During short intermissions in games players do not drink large volumes of fluid, because it is uncomfortable for them to do so, particularly because absorption of the fluid is slowed by high-intensity intermittent exercise, such as soccer.
The fluid replenishment will have very little impact upon the body temperature, as the ingested fluid will warm up to the temperature of the stomach within minutes.
More time, please
In terms of temperature regulation, a brief rest period will slow the rate of body heat gain because the muscular activity, which generates most of the heat, will be momentarily paused. But in such a brief period the significance of any heat loss is likely to be negligible at best.
Research in this area has led to some advances in this scientific field, with the ingestion of icy slushies in combination with the application of ice-cold, wet towels to the neck and head, producing promising early results.
Although such measures are easily administered on the field, we can expect minimal or negligible impact in such a short time period afforded by the proposed "cooling breaks".
A better solution to ensure player welfare - and to maximise commercial revenues - might be to increase the length of the half-time interval (currently 15 minutes in professional matches).
A recent survey demonstrated that by the time players return to the changing rooms and received coach instructions and/or medical treatment, there is very little time for anything else during the half-time break.
During this rest interval the players' body temperatures reduce by around 1C, and the players routinely ingest fluids, but this is not enough for the players to recover and adequately prepare for the physical rigors of the second half - particularly in hot conditions.
Increasing the half-time interval to 20 minutes would enable medical and sports science staff to implement more effective cooling and rehydration practises, perhaps even reducing body temperature to near pre-match levels.
Better for athletes (and advertisers)
While reducing the body temperature is beneficial for the prevention of HRIs, a prolonged rest period is not beneficial for the muscle, and we often see decline in the players' capacity to sprint and jump, together with an increased risk of muscular strain injuries at the start of the second half, when the muscle is cooler.
You may come to the conclusion that a longer half-time would therefore be counter-intuitive, but this additional time could be used effectively to both cool central body temperature, while also engaging players in activities to better prepare the muscles for the onset of the second half.
This improves performance and attenuates muscular strain risk (which accounted for 13.2% of match-induced injuries in the same American audit, or 35-fold more injuries versus HRIs).
From a revenue perspective, FIFA would gain from the increased advertising revenue, and also from increased refreshment purchases from fans who might actually have time to queue at the bar and return to their seats before the re-start.
A prolonged half-time interval is not a new concept to FIFA and is routine in AFL.
As a researcher in player performance, and a huge soccer fan, I'd urge them to re-consider a 20-minute half-time.
If they don't, how many questionable "cooling breaks" (complete with advertisements) will fans have to endure in a Qatar summer, nine years from now?
23 October 2013