Accuracy
The difference between winning and losing in sport can be minuscule, and even the slightest of errors can have a major impact on the outcome of an event. Accuracy is an integral part of success in many sports. For example, the ability to hit a double 20 in darts, hit a passing shot down the line in tennis, or kicking a field goal in rugby all require precision.
Research has illustrated just how important sleep is for performance accuracy. Edwards and Waterhouse (2009) completed a study investigating the effect of restricted sleep on the accuracy and consistency of dart throwing. The researchers compared the dart throwing performance of 60 participants after a normal nights sleep (7-8 hours), with their performance after a night of restricted sleep (3-4 hours).
The participants were asked to throw 20 darts at a target, where they received a higher score for a dart landing closer to the centre. A score of 10 points was given for hitting the bullseye, with the score reducing to 1 point for the outer ring (see image), and a score of 0 for missing the board completely.
The results showed that after a night of restricted sleep, the participants average score was only 3.61, compared to 4.16 after a normal nights rest. Thus, restricted sleep led to a 14% drop in performance! When sleep deprived they were also 1.3 times more likely to miss the target completely, and were more inconsistent with their throwing.
Reyner and Horne (2013) studied the serving ability of 16 semi-professional tennis players, and found that a reduction in sleep reduced accuracy in a serving task by over 40%. The task was to serve 40 balls and hit at a pre-defined target (see image). Participants were tested after normal sleep (6.5 to 8 hours) and after restricted sleep (5 hours).
A similar study by Schwartz and Simon (2015) also looked at tennis serving accuracy, but focused on the effects of sleep extension rather than sleep deprivation. They measured the participant’s sleep habits for a week to gain a baseline measure, and established they slept on average 7.14 hours per night. For the following week, the participants were instructed to try and increase their sleep to 9 hours per night. They actually managed to extend their sleep to 8.85 hours per night, and the increase in sleep (1.71 hours) improved their serving accuracy from 35.7% to 41.8%.
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Sleep extension was also shown to improve the free-throw and 3 point shooting accuracy of a Stanford University basketball team. Mah, Mah, Kezirian, and Dement (2011) firstly established baseline sleep patterns over a 2-4 week period. This was followed by a 5-7 week period where the participants were instructed to sleep as much as possible (at night), with the aim of achieving at least 10 hours per night. Sleep increased from 7.8 (baseline) to 10.4 (sleep extension) hours per night. The additional sleep led to an increase in free-throw success and 3 point shooting during a practice session by 9% and 9.2% respectively.
The results suggest that sleep deprivation decreases performance accuracy, while sleep extension increases it. This finding is especially important for athletes in sports where success is heavily influenced by accuracy, e.g. darts, tennis, golf, bowling, shooting, etc, etc, etc. There are plenty!
MODULE SLEEP
The impact on performance
The Impact of Sleep on Performance
Injury
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Reaction Time
Mood
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References
Edwards, B.J, & Waterhouse, J. (2009). Effects of one night of partial sleep deprivation upon diurnal rhythms of accuracy and consistency in throwing darts. Chronobiology International, 26 (4), 756-768.
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Mah, C.D., Mah, K.E., Kezirian, E.J, & Dement, W.C. (2011). The effects of sleep extension on the athletic performance of collegiate basketball players. Sleep (34), 7, 943-950.
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Reyner, L.A., & Horne, J.A. (2013). Sleep restriction and serving accuracy in performance tennis players, and effects of caffeine. Psychology and Behaviour, 120 (4), 93-96.
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Schwartz, J., & Simon, R.D. (2015). Sleep extension improves serving accuracy: A study with college varsity tennis players. Physiology & Behaviour, 151, 541-544. Chronobiology International, 31 (10), 1160-1168.