NJCAA kicked off its season yesterday, NCAA starts on Monday, and the NBA already has major issues with players missing games for rest in the first week of its season, so I wanted to highlight a study on substitutes.
Basketball differs from many sports because players sit on the bench and run straight off the bench and into the action. Soccer players generally warm up on the sideline in anticipation of entering the game, and volleyball and football players stand throughout games, offering opportunities to move and space to warm up; volleyball substitutes often move onto the court at timeouts and breaks and pepper to warm up their arms and skills. Basketball players are prohibited from leaving the bench at timeouts or quarters; teammates do not run on the court and hurry through a 60-second shooting drill at the timeout or run a few sprints. These are the rules and the culture of the sports, at least partially due to the constraints of the courts or fields, as the smaller volleyball court affords more room to spread out than a basketball court.
A study by Crowther and associates (2017) measured the countermovement vertical jump (CMVJ), skin temperature, core temperature, and heart rate (HR) of male semi-professional basketball players prior to their pregame warmup, after the warmup, and during the first half of the game. The researchers found the warmup worked: The players showed increases to their CMVJ, skin and core temperatures, and HR. Warmups generally are set up to achieve these performance and physiological responses. The responses were expected.
The purpose of the research, however, was to examine the effects of sitting on the bench prior to entering the game. The researchers found the performance and physiological responses declined below the baseline (prior to the warmup) for most measurements, depending on the rest time before entering the game.
The CMVJ dropped below the pre-warmup performance by halftime, whereas the core temperature declined from post-warmup, but remained elevated from pre-warmup throughout the half. Skin temperature peaked between six and eleven minutes after warmup and declined thereafter. By six minutes into the first quarter, the HR had dropped to pre-warmup levels with further decreases until halftime.
Another study found a relatively fast decline in jumping and running performance when basketball players remain inactive after warmup, which accompanied gradual decreases in body temperature and CMVJ (Galazoulas et al., 2012).
The findings suggest substitutes are not physically prepared to enter the game after sitting on the bench for prolonged periods. Essentially, they might as well skip the pregame warmup, physiologically, if they do not enter the game in the first six minutes, preferably, or at least in the first quarter.
To improve performance, coaches may look to make quicker substitutions to prevent players from sitting on the bench for prolonged periods and/or advise players to warm up quickly before entering the court, possibly using the exercise bicycles that often are found near team’s benches. Otherwise, players may be wise to create a quick warmup when entering on a dead ball situation, such as a free throw. Players may have time to engage in a few quick tuck jumps or ice skaters or a quick sprint to begin the warm up process as opposed to walking onto the court, standing and waiting for the action to resume.
These were small sample studies, so the findings are far from definitive. Some players may react better physically, physiologically, and psychologically to coming off the bench; others may be worse. However, the trend from this study and other sports suggests coaches should attempt to do more to prepare substitutes to enter the game for potential performance and injury prevention benefits (not studied).
Reference
Crowther, R.G., Leicht, A.S., Pohlmann, J.M., & Shakespear-Druery, J. (2017). Influence of rest on players’ performance and physiological responses during basketball play. Sports, 5(2), 27.
Galazoulas, C., Tzimou, A., Karamousalidis, G., & Mougios, V. (2012). Gradual decline in performance and changes in biochemical parameters of basketball players while resting after warm-up. European Journal of Applied Physiology, 112, 3327-34.
Or, as the picture shows, jump rope for 50 revolutions. That can be done in less than 30 seconds by a competent skipper. Surely the coach can just nod, or give a thumb's up to a bench player to do that?