Graphite shafts reduce forearm muscle activity in golf – a prospective case series of 40 right-handed amateur and professional golfers

Abstract Background Lateral and medial epicondylitis are common overuse injuries in golf affecting both amateur and professional players. Treatment options include medical but also non-medical interventions like optimizing golf equipment. While several studies have investigated the impact of grip size and style as well as the use of a golf glove on forearm muscle activity, the impact of shaft material remains unclear. Thus, aims of this study were (1) to assess the impact of different shaft material on the forearm muscle activity across the 5 phases of the golf swing, (2) to evaluate the effect on the individual performance and (3) to identify subgroups that may benefit more or less from this intervention. Methods A cohort of 40 golfers (mean age: 51 years; mean handicap: 16), completed 5 golf swings with a steel and a graphite shaft, respectively. Muscle activity of the M. extensor carpi radialis brevis (ECRB), M. flexor carpi ulnaris (FCU), M. pronator teres (PT) and M. biceps brachii (BB) in both the lead and the trail arm were evaluated using surface electromyography (EMG). Golf performance was measured with a Trackman device (Trackmangolf, Vedbæk, Denmark). Subgroup analyses were performed with regard to gender, playing ability (handicap < 10 vs. ≥10), preexisting elbow pain during golf (visual analogue scale (VAS) < 2 vs. VAS ≥ 2) and grip style (overlap vs. interlock vs. baseball). Significance was set at p < 0.05. Results During the final swing phase, the late follow-through, a graphite shaft leads to lower muscle activity in the FCU ( p = 0.027) and the PT ( p = 0.009) of the lead arm. Regarding grip style, the FCU of the trail arm showed higher muscle activity using a steel shaft ( p = 0.021). In golfers without preexisting elbow pain, a steel shaft caused higher PT muscle activity in the lead ( p = 0.002) as well as the trail arm ( p = 0.032). Conclusion Graphite shafts reduce forearm muscle activity in golf and may serve as a non-medical treatment for overuse injuries like lateral and medial epicondylitis. Trial registration The study was registered in the German Clinical Trials Register as “The Impact of Shaft Materials on Upper Limb Muscle Activity in Golf” DRKS-ID: DRKS00036063. Retrospectively registered on February 3, 2025.