Half time in sport: should you warm up or cool down?

Half-time therapies to combat second half fatigue and injury

What half-time therapies are available to combat second half fatigue and injury? Matt Lancaster looks at the physiological benefits of half-time cooling and warm-ups…

One of the paradoxical challenges faced by coaches at half-time is how to recover from the first half while simultaneously preparing for the second half. In short, should you be cooling your squad down or warming them up? When it comes to half-time recuperation, any therapies that are used should ideally enhance performance in the second half as well as reduce the impact of injury and the incidence of further injuries. Looking to see what the science says is obviously important, but so is an intimate knowledge of your chosen sport. Considerations such as the length of the half-time period, the rules on substitution and the likely injury risks of that sport will all impact on how applicable any scientific research is to your sport.

Cooling strategies

When the heat is on, a number of sophisticated cooling techniques can be use to lower core temperature. These include contrast water therapy, pre-cooling and ice bath immersion. However, just because they’re popular with elite endurance athletes doesn’t mean they’ll work in the half-time period for team sportsmen and women. Unlike endurance sports, team sports involve hugely varying intensities, and different playing positions and levels within a sport can alter the cooling requirements.

A US study comparing cross-country runners and American Footballers for example showed that core temperatures in the footballers rose and fell in line with the level of activity, while the runners’ core temperatures rose steadily and stayed elevated1. Another study compared core temperatures of recreational footballers with professionals playing in the English Championship league2. The recreational players showed rises in core temperatures through the first and second halves, with a drop to near normal levels at half-time. The pros however had a more modest core temperature rise during the first half, which then stabilised during the second half – probably because they were better heat-acclimatised than the recreational players.

In more general terms, the degree of core temperature rise and the amount of half-time cooling required will depend on a variety of factors. These include:

•    The temperature of the environment;
•    The position you play in and the level you play at;
•    The typical variability of intensity of your sport;
•    Your degree of heat acclimatisation;
•    The degree of muscular fatigue you feel (fatigue reduces your work out and therefore lessens the rise in core temperature).

Practicalities of cooling

A half-time cooling strategy may be useful, especially on hotter match days; it may help to delay the rise in core temperature in the second half, which temporarily helps to trick the brain into thinking you are fresher than you are. However, probably one of the biggest benefits is to make you more comfortable during the half-time break, allowing you to focus and remember more clearly on what the coach is saying!

There are also the practicalities to consider; a 60-minute cooling session to significantly lower core temperature is impossible in a 15-minute half-time break! However, research has shown that shorter cooling sessions can improve your self-paced performance even when core temperatures are not lowered3.

Unfortunately, most studies on cooling have looked at pre-cooling, not cooling between bouts of intense exercise, although one more recent study has shown that 12 minutes of immersion in cold water between bouts of exercise improved running performance4. But even this is likely to be impractical for a team of 11 or 15 players during a break of just 10-15 minutes! A more realistic approach is to remove protective clothing, use ice-packed towels around the shoulders, submerging hands in cold water and change into fresh kit for the start of the second half.

If there are questions over injury, the coach and player should ice immediately and wait for the club physiotherapist or doctor to assess the situation. If this is not possible, you should ask yourself 2 questions:
•    Is the discomfort too severe to enable you to make a full contribution in the second half?
•    Could you make the injury significantly worse in the longer term by continuing to play?
If the answer to either question is yes, it’s probably not worth continuing.

What about warm-ups?

You may intuitively think that warming up before the second half makes sense. However, if this were true, the majority of injuries should occur early in each half because the players will become gradually warmer as each half progresses. But data collected by the English FA on the timing of hamstring and ankle strains in footballers flies in the face of this theory5,6. Almost half of the reported injuries occurred during the last 15 minutes of each half. And the period immediately following half time was actually identified as the lowest injury risk period in the match!

These data are supported by a study on injury timing in Rugby Union players where the majority of injuries occurred during the latter stages of each half, especially towards the end of the second half7. A similar study in Australian Rugby League players playing 3 or 4 ‘sevens’ matches in a single day showed that the risk of injury rose steadily from the first to the last match. The only possible conclusion in the light of these studies is that fatigue presents a much greater risk than not warming-up properly before the second half.

In addition to adequate fluid and carbohydrate, the best way of combating fatigue during half-time may be to remain motivated and set the appropriate arousal level before the start of the second half, which may even mean calming down! Waking up you central nervous system just before the start of second half is also worth considering, perhaps by series of short maximal sprints as you return to the pitch.

References:

(1)    J Athletic Training 2004; 39 (3): 235-240
(2)    Br J Sports Med 2006; 40: 133-138
(3)    J Sports Sciences 1999; 17: 937-944
(4)    J Strength & Conditioning Research 2006; 20 (2): 383
(5)    Br J Sports Med 2004; 38: 39-41
(6)    Br J Sports Med 2003; 37: 233-238
(7)    Br J Sports Med 2005; 39: 757-766
(8)    Br J Sports Med 2002; 36: 23-26

Original article by Matt Lancaster; summary by Andrew Hamilton BSc Hons MRSC ACSM

Get on the road to gold-medal form and smash your competition.
Try Peak Performance today for just $1.97.

Tagged in warm up
Privacy Policy [opens in new window]
Please Login or Register to post a reply here.