T
Gerasimos V Grivas*
School of Physical Education and Sports Science, Greece
*Corresponding author: Gerasimos V Grivas, School of Physical Education and Sports Science, Greece
Submission: October 14, 2019;Published: October 31, 2019
ISSN 2637-7934 Volume2 Issue5
Detraining is the reduction of performance that happens after the cessation of training and is reflected by anatomic and physiologic changes. The purpose of this study was to investigate the effects of reduce training on cardiovascular parameters in distance runners. Many studies showed reduce of VO2 max and anaerobic threshold after detraining. On the other hand, only one study examined the effect of detraining on running economy and did not observe a decline.
Keywords:Detraining; VO2 max; Anaerobic threshold; Running economy; Distance runners
Detraining is the partial or complete loss of training-induced adaptations, in response to an insufficient training stimulus [1]. In general, significant conditioning is lost after 2-6 weeks of insufficient training. In other words, the individual becomes ‘less fit’ [2]. Therefore, recognizes that stopped, or reduction of a training stimulus leads to a decline in specific conditioning. The rate of ‘fitness’ decrement with training cessation does vary from one physiological parameter to the another and so are here divided logically. The most important parameters that are affected from reduce training or detraining is maximal oxygen uptake (VO2max), anaerobic or lactate threshold and running economy. Therefore, the purpose of this study was to investigate the effects of reduce training on cardiovascular parameters in distance runners.
When runners don’t train for a couple of weeks, the resulting drop in VO2 max is caused primarily by a loss in plasma volume, which is a key aspect of detraining. More specifically, the study of Houston et al. [3] showed that 15 days of inactivity led to 4% reductions in VO2 max in well-trained endurance runners. Moreover, Houmard et al. [4] & Houmard JA et al. [5] reported that VO2 max also decreased by 4.7% in a group of endurance-trained runners after 14 d of training cessation. Also, Coyle et al. [6] showed that 2-4 weeks of stopped training in eight endurance trained subjects reported 6% VO2 max declined during upright exercise. Furthermore, Mankowitz et al. [7] studied a group of trained runners who stopped training for 14-22 days and reported 12% VO2 max declines. In a similar study, Martin et al. [8] showed that after of 3-8 weeks physical deconditioning in highly trained runners VO2 max reduction by 20%. Coyle et al. [9] observed that seven endurance-trained subjects stopped training for 84 days, and their VΟ2max declined by 7 and 16% in 21 and 56 days, respectively, it then stabilized at that level, which was still 17.3% higher than that of sedentary control subjects. In conclusion, many studies indicate that VO2 max of highly trained athletes decreases progressively and proportionally to the initial VO2 max during the first 8 week of training cessation [10,11].
Only a few studies examined the effect of detraining on anaerobic and lactate threshold. In the study of Ready et al. [12] reported that 9 weeks of training is of sufficient duration to cause a significant alteration in anaerobic threshold. Loss of this training gain occurs rapidly and appears to be similar to changes in VO2 max. Coyle et al. [13] examined the effects of detraining after 12, 21, 56 and 84 days. After detraining of 21, 56 and 84 days showed reduce of anaerobic threshold by 11.5%, 20.3% and 23.5% respectively. Pavlik et al. [14] reported on 40 observations on highly trained road cyclists and endurance runners who, for various reasons, stopped training for 60 days. They observed a linear decline in the athletes’ lactate threshold throughout the initial 45 days of training stoppage, with no further change thereafter.
Only one study examined the effect of detraining in running economy. Houmard et al. [4] did not observe a decline in running economy at submaximal exercise intensities (75 and 90% of VO2 max) in their 12 distance runners after 14 days of detraining, which suggests that the short-term training cessation-induced performance impairment was primarily because of the loss in cardiorespiratory fitness suffered by the athletes.
When physical training is markedly reduced or stopped for a period longer than 4 weeks, the VO2 max of highly trained athletes declines by 6 to 20%, but usually remains above sedentary values. Therefore after 21-84 days of detraining observed reduce of anaerobic threshold by 11.5-23%. Finally, after 14 days of detraining did not showed a reduce in running economy.
© 2019 Salem Bouomrani. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and build upon your work non-commercially.