It is important to investigate how the golf swing changes with extended play because fatigue affects the performance of athletes playing sports similar to golf. Golf is a physically demanding sport when playing 18 holes while walking and carrying a bag. The effect of playing 18 holes of golf on the mechanics and swing outcome of the golfer are currently unknown. The knowledge of how extended play affects the golf swing will aid golfers, golf coaches, and researchers in understanding proper golf training and play affected swing mechanics. This study investigates the effect of playing 18 holes of simulated golf on the mechanics and performance of the golfer. A total of seven male and female recreational golfers scoring between 80 and 95 on 18 holes of walked golf were recruited for 3-D motion analysis of 140 tee shots. Mechanical variables and outcome variables at three phases of the golf swing were tested over time to evaluate the relationship between time (playing golf), mechanical variables, and the outcome of the golf shot tested statistically using path analysis. Weight transfer to the lead leg at ball contact was significantly related to club head velocity (CHV). Over time, golfers were less able to achieve a weight transfer to the lead leg, which was directly related to the golfers' club head velocity. The lead knee and lead ankle angles were also affected by time, which had an influence on club head velocity. These results suggest that golfers do change their swing throughout the course of 18 holes of walked golf and there are key swing mechanics which significantly influence golf performance. / School of Physical Education, Sport, and Exercise Science

Not available / text

Two investigations were conducted with collegiate golfers for separate, but related purposes. 1) To investigate the effects of a physical conditioning program (strength, power and flexibility training) on clubhead speed, consistency, and putting distance control. 2) To investigate the effects of 36 continuous holes of competitive golf on testosterone and cortisol response and their relation to performance.Study #1: Subjects were ten men and six women NCAA Division I golfers. Supervised strength, power, and flexibility training was performed 3 times per week for 11 weeks. Golf ball launch conditions, putting distance control, strength, power, and flexibility tests were conducted before and after training. Significant (p < 0.05) increases were noted for all strength, power, and flexibility tests. Clubhead speed increased significantly (1.6%) from pre to post training, equating to a 4.9-meter increase in driving distance. No significant differences were observed for clubface-angle or launch-angle deviation. Putting distance performance significantly improved for the men-only group (29.6%). Significant (p < .05) correlations resulted between clubhead speed and rotational power (r = 0.86) for the men-only group. Qualitative video analysis did not show any consistent trends in swing mechanics alterations. Eleven weeks of physical conditioning increased clubhead speed without a negative effect on consistency or putting distance control in intercollegiate men and women golfers. Study #2: Subjects were eight NCAA Division I men golfers. Saliva samples were taken 45 minutes prior to the round and after each hole during a 36-hole competition. Time matched baseline samples were collected. Six and 36-hole area under the curve (AUC) values were calculated for endocrine measures. Salivary cortisol increased by 111% (p < 0.05) during competition compared to baseline. Testosterone-to-cortisol ratio was significantly lower (45%) throughout the competition compared to baseline. Significant (p < 0.05) correlations resulted between: 36-hole AUC testosterone-to-cortisol ratio difference and 36-hole score (r = 0.82), CSAI-2 somatic anxiety and pre-round cortisol (r = 0. 81), testosterone (r = -0.80), and testosterone-to-cortisol ratio (r = -0.72). These results indicate a significant hormonal strain during 10 hours of competitive golf, low TIC ratio relation with low golf scores, and CSAI-2 relation with endocrine measures. / School of Physical Education