Recovery is increasingly recognised as a significant component of athletic training and performance – particularly for elite performers, who may be expected to engage in very demanding training two or even three times a day. An adequate recovery is known to decrease fatigue, accelerate physiological regeneration, enhance adaptation and (possibly) decrease the risk of injury. So what is the best recovery strategy?Research overwhelmingly supports the superiority of active recovery (light exercise) over passive (resting) recovery for the removal of lactate – a by-product of strenuous exercise – from the circulation. However, the relationship of active warm-down with other measures of recovery – including subsequent performance – remains unclear.
And meanwhile there are newer kids on the recovery block – such as sports massage and various water therapies. Hot-and-cold (contrast temperature) water immersion, in particular, is currently being used as a recovery strategy by many athletes and coaches, although there has been very little research to substantiate its effectiveness.
This is a gap a team of researchers from New Zealand and the UK sought to fill with a comparison of the impact of active recovery (ACT), passive recovery (PAS) and contrast temperature water immersion (CTW) on repeated treadmill running performance, lactate concentration and pH – the latter implicated as a contributor to metabolic fatigue.
The study involved 14 highly active male volunteers, who completed the following testing protocol on three separate occasions: two treadmill runs to exhaustion, at 120% and 90% of peak running speed (PRS), separated by 15 minutes’ rest. On completion of the second run to exhaustion, participants were exposed to one of the three recovery strategies for 15 minutes, as follows:
- Active recovery (ACT) – running at 40% PRS on the treadmill;
- Passive recovery (PAS) – standing upright within an 80cm diameter circle;
- Contrast temperature water immersion (CTW) – alternating between 60 seconds cold and 120 seconds hot water immersion, starting with cold and ending with hot.
The following findings emerged from comparison of the three recovery strategies:
- the type of recovery used had no significant effect on performance in the subsequent test protocol. High intensity treadmill running performance had returned to baseline four hours after the initial exercise bout regardless of the trial condition used;
- post-exercise blood lactate concentration was lower with Active recovery (ACT) and contrast temperature water immersion (CTW) than with passive recovery (PAS);
- blood pH was not significantly influenced by recovery mode;
- participants reported an increased perception of recovery during contrast temperature water immersion (CTW) compared with active recovery (ACT) and passive recovery (PAS).
What can explain this effect? It is likely, they suggest, that the alternate dilation and constriction of the blood vessels with hot and cold water immersion boosts blood flow to the immersed muscles, thereby improving lactate removal.
Why was this beneficial effect on lactate not reflected in improved subsequent performance? Possibly because the time gap between recovery and performance was overlong at four hours. ‘The potential remains,’ argue the researchers, ‘that the type of recovery modality may have influenced performance if the second exercise bout had been performed closer to the first bout… Further research is required to ascertain the influence of contrast temperature water immersion on the time course for recovery of treadmill running performance.’
They conclude that contrast temperature water immersion (CTW) may be a better recovery strategy than active recovery for some athletes because similar physiological changes are achieved, with reduced exertion and increased perceptions of recovery.
J Sci Med Sport 2004;7;1: 1-10