RESUMEN
BACKGROUND: Historically, golf does not have a strong tradition of fitness testing and physical training. However, in recent years, both players and practitioners have started to recognise the value of a fitter and healthier body, owing to its potential positive impacts on performance, namely clubhead speed (CHS). OBJECTIVE: The aim of this meta-analysis was to examine the associations between CHS (as measured using a driver) and a variety of physical characteristics. METHODS: A systematic literature search with meta-analysis was conducted using Medline, SPORTDiscus, CINAHL and PubMed databases. Inclusion criteria required studies to have (1) determined the association between physical characteristics assessed in at least one physical test and CHS, (2) included golfers of any skill level but they had to be free from injury and (3) been peer-reviewed and published in the English language. Methodological quality was assessed using a modified version of the Downs and Black Quality Index tool and heterogeneity assessed via the Q statistic and I2. To provide summary effects for each of the physical characteristics and their associations with CHS, a random effects model was used where z-transformed r values (i.e. zr) were computed to enable effect size pooling within the meta-analysis. RESULTS: Of the 3039 studies initially identified, 20 were included in the final analysis. CHS was significantly associated with lower body strength (zr = 0.47 [95% confidence intervals {CI} 0.24-0.69]), upper body strength (zr = 0.48 [95% CI 0.28-0.68]), jump displacement (zr = 0.53 [95% CI 0.28-0.78]), jump impulse (zr = 0.82 [95% CI 0.63-1.02]), jumping peak power (zr = 0.66 [95% CI 0.53-0.79]), upper body explosive strength (zr = 0.67 [95% CI 0.53-0.80]), anthropometry (zr = 0.43 [95% CI 0.29-0.58]) and muscle capacity (zr = 0.17 [95% CI 0.04-0.31]), but not flexibility (zr = - 0.04 [95% CI - 0.33 to 0.26]) or balance (zr = - 0.06 [95% CI - 0.46 to 0.34]). CONCLUSIONS: The findings from this meta-analysis highlight a range of physical characteristics are associated with CHS. Whilst significant associations ranged from trivial to large, noteworthy information is that jump impulse produced the strongest association, upper body explosive strength showed noticeably larger associations than upper body strength, and flexibility was not significant. These findings can be used to ensure practitioners prioritise appropriate fitness testing protocols for golfers.