Tuesday, March 11, 2014

Player Perceptions of Artificial Turf

The use of artificial turf (AT) playing fields continues. Despite recent research on performance and health issues surrounding AT, debate over injury risks and heat still swirl around the topic of “playing on plastic”. The safe use of AT is a complex issue and perceptions can influence how players perform as well as their susceptibility to injury. A recent study shows that professional players generally view AT negatively and feel that it raises the risk of injury and results in more delayed-onset muscle and joint soreness. Some of their perceptions may be rooted in evidence while some may not. However, it is important for coaches and trainers to understand how players feel about playing and training on AT.

The researchers collected surveys from 99 professional players from six MLS teams. They asked them to recall their experiences playing on AT and grass.

The survey yielded some important findings:

  • 97% felt that playing and practicing on AT resulted in greater muscle and joint soreness.
  • 90% felt that it took more time to recover after playing a match on AT.
  • 94% felt that AT raised their risk of sustaining an injury.
  • Most players felt that AT was stiffer, had greater friction and exacted a greater metabolic cost than grass.
  • A large percentage agreed that the quality of the AT was an important factor in injury risk.

Overall, players had a negative perception of AT. They felt that AT increased the risk of injury and resulted in greater muscle fatigue and soreness. These perceptions seemed to be due to the mechanical properties of the turf.

The authors of the study mentioned that pre-established bias and personal experience may have shaped their opinion of AT. No doubt that a large percentage of public comments made by athletes and in the press about AT is negative. This can easily shape ones opinion of a particular playing surface. Also, comments provided by the players suggested that many have had negative experiences on AT: “All my 3 biggest injuries have happened on turf matches”, “Coming off back-to-back ACL tears… I feel mentally scared to play on turf”, “fear of having a cleat stick in the turf” and “The first time I played on (turf), I broke my 5th metatarsal”. Thus, it’s not surprising that players generally view AT negatively.

Are the player’s perceptions of increased injuries correct? We recently conducted a review of eight research studies looking at the rate of injuries on AT and grass. We found that playing or training on AT did not raise the risk of injury. This held for male and female players and for young and adult players. In fact, some injuries were actually lower on AT. Thus, from a research perspective, there is no evidence that playing on AT results in more injuries. However, this is a complicated issue.

Earlier research suggests that the player’s perception of greater fatigue and effort may be correct. The game does change when played of AT. Ball movement, passing sequences and playing tactics are different on AT compared to grass. For example, more short passes are attempted on AT along with fewer slide tackles. This is something that could increase effort, cause more fatigue and increase delayed-onset muscle soreness.

Fatigue along with muscle and joint soreness that persists 24-48 hours after a match can impact both performance and injury risk. In youth and college competitions, multiple matches are often played with limited time for recovery. There’s little debate that fatigue raises injury risk. If fatigue and soreness, either real or perceived, is greater after competing on AT, there is the possibility that injuries could occur during subsequent match, whether played on grass or AT. Regardless of the surface, injury risk may be increased due to greater fatigue or changes in movement patterns resulting from soreness.

Unfortunately, we could find no research on muscle soreness or markers of muscle damage after playing on AT. Injury studies classify an “injury” as something that prevents a player from participating for at least one day. While muscle soreness may hinder play, it usually doesn’t force a player to the sideline or count as an injury. Thus we can’t confirm the player’s perceptions of muscle and joint soreness after playing on AT. Neither can we discount them.

The authors of the study point out that it is important to understand player perceptions of AT. For example, if players routinely report more fatigue during the match as well as muscle and joint soreness 24-48 hours after a match, coaches can make adjustments in playing time and training schedule. Strategic substitutions and increased recovery may help players avoid injuries that result from short- and long-term fatigue. This is particularly true for teams where a Friday-Sunday schedule is played.

This study will not end the debate over playing and training on AT. It does confirm what many have long felt, many players prefer playing on natural grass and feel that it is a safer surface. It also emphasizes the need for more in-depth research into the use of AT fields. Understanding issues such as delayed onset muscle or joint soreness, effects of a congested calendar and long-term fatigue can go a long way in either confirming or allaying player perceptions.

Reference

Poulos CCN, Gallucci J, Gage WH, Baker J, Buitrago S, Macpherson AK (2014) The perceptions of professional soccer players on the risk of injury from competition and training on natural grass and 3rd generation artificial turf, BMC Sports Science, Medicine and Rehabilitation, 6:11