TRUNK ROTATION AND THE DISTANCE A GOLF DRIVE

The Relationship between Trunk Rotation and the Distance A Golf Drive

TABLE OF CONTENTS

CHAPTER 1: INTRODUCTION3

C|HAPTER 2: LITERATURE REVIEW6

Relationship between swing performance and skill (handicap and score)6

Relationship between muscle strength and skill (handicap and/or golf score)7

Relationship between muscle strength and swing performance8

Changes in swing performance as a consequence of strength training11

CHAPTER 3: METHODS13

Subject Recruitment13

Subjects14

Testing procedures14

Strength Testing15

Endurance Testing16

Strength Test Reliability17

Data Analysis17

Strength Test Reliability17

Rotational Strength Data18

Rotational Endurance Data18

Range of Motion of Torso Rotation18

Correlation Analyses18

REFERENCES20

CHAPTER 1: INTRODUCTION

The effective execution of the golf swing not only requires rapid movement of the extremities but also substantial strength and power of the trunk muscles. The torso rotates away from the target (to the right for a right handed player) at approximately 85 deg/sec on the backswing while the powerful downswing involves trunk velocities approaching 200 deg/sec. Pink et al demonstrated relatively high and constant activity in the abdominal oblique muscles throughout most parts of the golf swing of skilled amateur players. In a similar study using professional golfers, Watkins et al measured muscle activity in the erector spinae, abdominal oblique, and rectus abdominis (Parnianpour, 1998: 2563). These authors established that all trunk muscles were relatively active during the acceleration phase of the golf swing with the trail-side abdominal oblique muscles showing the highest level of activity.

Given the relative importance of the trunk muscles in golf, particularly in terms of generating powerful axial rotation on the downswing, repetitive play and practice might contribute to enhanced rotational strength and endurance amongst these athletes. Furthermore, this asymmetric pattern of trunk rotation during the golf swing (slow rotation backswing followed by high velocity downswing) may cause side-to-side imbalances in rotational strength and endurance characteristics amongst elite players who frequently play and practice. These potential imbalances may contribute to an increased susceptibility of developing low back pain. Lindsey and Horton have shown side-to-side maximum trunk rotation flexibility imbalances in elite golfers with and without low back pain (LBP) (Lindsay, 2002: 599).

The authors of this study are aware of only six peer-reviewed, non golf-related, research studies that have evaluated strength and endurance characteristics of the trunk muscles during axial rotation movements (Kumar, 1997: 2213). Three of these studies have reported isokinetic trunk rotation strength measures, while the others attempted to assess trunk muscle characteristics with electromyography (EMG) during repeated trunk rotations. Five different studies have investigated strength and or endurance parameters during trunk flexion and extension motions. A limitation of most of these studies was they used custom made equipment to collect data. Kumar reported that the scarcity of data for trunk rotation is directly attributable to the lack of suitable, accurate, standardized, and affordable devices to permit such measurement (Kumar, 1997: 2213). Consequently, gaps in the literature exist regarding trunk rotation strength and endurance capabilities in the general population. Furthermore, no previous studies have investigated trunk rotation strength and endurance in golfers.

Suter and Lindsay compared static trunk extensor endurance and inhibition of the quadriceps in low handicap golfers with LBP and healthy age-matched controls who did not ...