Jump as a Fatigue Indicator
The monitoring of neuromuscular fatigue in athletes is very relevant when planning training sessions and competitions.
Recovery between sessions is extremely important for high training loads in professional sports. If the rest period is not appropriate, this could result in the athlete not being able to perform the amount of work required to produce the adaptations that eventually lead to improved performance. Because of that, optimising the recovery strategies is one of the main tasks for coaches and trainers.
In this context, one of the most popular recovery methods is immersion in cold water, which involves partial or total immersion in water at a temperature of 10-15ºC during 5-20 minutes.1 It has traditionally been hypothesised that cold water accelerates recovery after a training session, which could possibly contribute to maximising adaptive responses chronically. Although cold water is an effective method to reduce pain within 24 hours after training,2 showing that it can be an effective method to greatly reduce fatigue, there are other mechanisms induced by cold water that could also reduce training adaptations. Two of these mechanisms are the reduction of blood flow and inflammation. Cold induces a vasoconstrictor response and subsequent decrease in blood flow that decreases the amino acid transport and, therefore, muscle protein synthesis,3 thus contributing to a reduction of muscle hypertrophy and strength development. Also, the reduction of the inflammatory response associated with cold could limit an essential mechanism of the muscle recovery process after training, which would result in lower muscle mass gain in the long term. For example, a study published by Roberts et al. in 2015 compared the effects of immersion in cold water (10 minutes at 10ºC, immersion of legs up to the waist) and the active recovery (bicycle at low intensity) on changes in muscle mass, strength and satellite cells (muscle stem cells) activity in a strength training program.4 After 12 weeks of training, researchers observed that those who recovered with cold water had significantly reduced training adaptations, apart from having lower mass gain and muscle strength and a reduction of key proteins in muscle synthesis and the activation of satellite cells for up to 2 days after training.
Consequently, one might think that, due to reduction in adaptations associated with training, using cold water as a recovery method could harm performance in strength sports. However, what about endurance sports? To answer this question, a recent meta-analysis published in the prestigious Sports Medicine journal has analysed the impact of the use of cold water in both strength and endurance sports performance.5 The results showed that the regular use of immersion in cold water decreases parameters of strength performance, such as 1-RM (1 maximum repetition), isometric strength, strength-endurance (measured in number of repetitions) or power in ballistic movements such as jumping. Regarding parameters related to endurance sports, immersion in cold water does not affect performance in the time trial or the maximum aerobic power. It means that these results suggest that cold water would affect strength sports performance, but not the endurance ones. One possible explanation suggested by researchers that would prove the lack of effect of immersion in cold water on performance in endurance sports would be that peripheral changes of muscle function could have less impact than main adaptations (cardiovascular function).
With that said, the hypothesis that immersion in cold water could produce greater long-term adaptations for a better recovery would be dismissed, since the evidence suggests that immersion in cold water does not induce improvements in endurance sports, and it reduces some of the main performance parameters in strength sports.
Cold water as a method of recovery seems to be effective when reducing pain and fatigue after training, which is why in some cases, its use could be of interest. For instance, in tournaments where matches are played on consecutive days, immersion in cold water could be justified, since, in this case, the objective is short-term performance, not future adaptations. Instead, especially in those sports in which strength and power are essential parameters in performance, it could reduce long-term adaptations due to the physiological mechanisms it triggers: reduction of blood flow and inflammation and, as a consequence, reduction of the activation of satellite cells and molecular pathways involved in muscle regeneration and hypertrophy. Muscle damage induced by exercise stress is necessary in processes of recovery and improvement of muscle function, which is why recovery methods such as cold water could endanger adaptations associated with the training process, especially in strength sports.
Adrián Castillo García
Although there are several studies on this topic, many of them have analyzed these demands by looking at just a few variables or using very broad timeframes. A new study completed by physical trainers from F.C. Barcelona has analyzed several of these details more closely.
The understanding of the modifying variables of the game, based on the degrees of freedom.
Training using eccentric exercises is important to prevent possible damage. However, intensive training can also cause muscle damage, so it is critical to be vigilant in order to keep injury risk to an absolute minimum.
The importance of building a game model in football.
Cardiovascular endurance manifests as a moderator of the load result to which the athlete is exposed.