ACSM usually posts the supplement issue of abstracts from their annual meeting on their journal website, but as of this morning it was not online. You would typically need a password to get at it anyway, so I've take the liberty of reproducing it here:
Effects of 18 Holes of Simulated Golf on the Performance of Recreational Golfers
Nick R. Higdon, Eric Dugan. Ball State University. Muncie, IN. Email: nhigdon@ballstate.bsu.edu (No relationship reported)
The mechanics of the golf swings have been investigated to determine what aspects of the swing are most important to performance. However, there is little research focused on how the golf swing changes throughout a round of golf.
PURPOSE: The purpose of this study was to determine the relationships between time (playing 18 holes of walked golf), mechanical variables, and performance variables related to the golf swing. The mechanical variables included ground reaction forces bilaterally; sagittal plane ankle, knee, and hip angles, angular velocity of the pelvis and thorax, and their relative timing. The performance variables were club head velocity and shot consistency.
METHODS: One female and six male recreational golfers scoring between 80 and 95 while playing 18 holes of walked golf participated in the study. Each golfer participated in a protocol designed to simulate walking and playing 18 holes of golf. The participants walked 6 miles, in 1 mile increments, while carrying a weighted bag. Before the first mile walked, and after each subsequent mile walked, the golfers hit 20 tee shots, totaling 140 tee shots at the conclusion of the protocol. Kinematic and kinetic data were captured on every swing. The relationship between time, mechanical variables, and the outcome of the golf shot were tested statistically using path analysis.
RESULTS: Weight transfer to the lead leg at ball contact was significantly related to club head velocity. Over time, golfers were less able to achieve a weight transfer to the lead leg at ball contact, which was directly related to the golfers’ club head velocity. The lead knee and lead ankle angles at the top of the swing were also affected by time, which had an influence on performance.
CONCLUSIONS: 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. Of the variables examined, the position of the lead knee and lead ankle at the top of the swing, and the weight transfer to lead leg at ball contact, were found to be the most important contributors to swing performance while playing 18 holes of simulated golf.