Date Published: June 29, 2017
Publisher: Public Library of Science
Author(s): Eduardo Abade, Jaime Sampaio, Bruno Gonçalves, Jorge Baptista, Alberto Alves, João Viana, Luca Paolo Ardigò.
Warm up routines are commonly used to optimize football performance and prevent injuries. Yet, official pre-match protocols may require players to passively rest for approximately 10 to 15 minutes between the warm up and the beginning of the match. Therefore, the aim of this study was to explore the effect of different re-warm up activities on the physical performance of football players. Twenty-Two Portuguese elite under-19 football players participated in the study conducted during the competitive season. Different re-warm up protocols were performed 6 minutes after the same standardized warm up in 4 consecutive days in a crossover controlled approach: without, eccentric, plyometric and repeated changes of direction. Vertical jump and Sprint performances were tested immediately after warm up and 12 minutes after warm up. Results showed that repeated changes of direction and plyometrics presented beneficial effects to jump and sprint. Different practical implications may be taken from the eccentric protocol since a vertical jump impairment was observed, suggesting a possibly harmful effect. The absence of re-warm up activities may be detrimental to players’ physical performance. However, the inclusion of re-warm up prior to match is a complex issue, since the manipulation of volume, intensity and recovery may positively or negatively affect the subsequent performance. In fact, this exploratory study shows that eccentric exercise may be harmful for physical performance when performed prior a football match. However, plyometric and repeated changes of direction exercises seem to be simple, quick and efficient activities to attenuate losses in vertical jump and sprint capacity after warm up. Coaches should aim to develop individual optimal exercise modes in order to optimize physical performance after re warm activities.
Warm up (WU) routines prior to exercise are widely explored by literature and commonly accepted for optimizing performance. Such routines include short-duration and high-intensity activities that intend to enhance physical predisposition by increasing intra-muscular temperature, nerve conductance rate and metabolic reactions . In fact, it is well documented that muscle performance can be acutely improved following a preloading maximal or near maximal stimulus due to the induction of post-activation potentiation . Although physiological readiness and injury prevention seem to be consensual outcomes of the WU, its structure and protocols used are still controversial. Moreover, there is still a disconnection between evidence-based methods and on-field practices.
Individual and mean changes from post-WU to R-WU in considered performance measures are shown in Fig 2. Complementary, Fig 3 and Table 1 presents the standardized differences and practical inferences, respectively, based on the pre-post crossover trial analysis.
This study shows that the absence of R-WU activities in the time gap between the end of the WU and the beginning of the match may impair the players’ physical performance. While performing eccentric exercise before a football match may be even harmful, losses in power output are attenuated by performing active R-WU exercises such as plyometrics and repeated changes of direction. In fact, the PLY and RCOD interventions tested in this study showed to be important acute post activation potentiation activities in both vertical jump and sprint capacity. This may be due to the fact that different and specific post activation potentiation regimens may optimize related functional tasks by improving performances in similar force-orientation production .
This study explored the acute effects of R-WU performed in the time gap between the end of the WU and the beginning of the match. The major findings were:
The mode of the conditioning exercise, intensity, recovery time, type of contraction as well as the players’ training status will determine an individual response in either potentiating a subsequent exercise task or inducing fatigue [38, 39]. Under this scope, research suggests that, generally, post activation potentiation mechanisms WU effects are more efficient in well trained individuals rather than in recreational athletes, probably due to their capacity to recruit more motor units at a higher firing rate during the conditioning exercise . For this reason, coaches should determine each individual’s optimal exercise mode in order to optimize the positive effect of the R-WU activity in players’ performance response after the WU. PLY and RCOD are efficient post activation activities that induce acute positive effects in both vertical jump and sprint capacities. Future investigations should be focused on the effects that different R-WU activities may have across the 90 minutes of a competitive match.