Fifty athletes were tested.  They were divided into two groups.  One group received chiropractic adjustments, the other served as controls.  Eleven tests were used to measure aspects of athletic ability including:  agility, balance, kinesthetic perception, power and reaction time.  After 6 weeks, the control group exhibited minor improvement in eight of the 11 tests, while the chiropractic group improved significantly in all 11 tests.  In a hand reaction test measuring the speed of reaction with the hand in response to a visual stimulus, the control group exhibited less than a 1% response while the chiropractic group exhibited more than an 18% response after 6 weeks.  After 12 weeks, the chiropractic group exhibited more than 30% improvement.  Chiropractic effects on athletic ability.  Lauro A. Mouch B.  Chiropractic:  The Journal of Chiropractic Research and Clinical Investigation.  1991; 6:84-87.

The athletic performance of university baseball players was assessed before, during and after chiropractic care.  Each athlete's performance was evaluated by athletic abilities, such as the vertical jump and standing broad jump, linear space, muscle strength; and physiological tests such as electrical cardiogram, blood pressure, pulse rate and treadmill stress testing.  28 players were recruited for the study.  Twenty players completed the entire experiment with usable data.  All players were randomly divided into control and experimental groups.  Every player was required to complete three sessions of athletic ability and physiological tests.  The first test was administered before any chiropractic care was given.  The second test was given after six weeks of care.  The third test was given after fourteen weeks of care.  Only the subjects in th experimental group received chiropractic adjustments to remove/reduce vertebral subluxation.  The results showed a positive correlation between chiropractic adjustments and athletic performance.  In addition to the above improvements, the chiropractic group showed significant improvement in capillary count at five and fourteen weeks of chiropractic care. Athletic performance and physiological measures in baseball players following upper cervical chiropractic care:  a pilot study.  Schwartzbauer J, Kolber J, Schwartzbauer, DC, Hart, JDC, Zhang J.  J of Vertebral Subluxation Research 1997; 1(4); 7.

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