Analysis of a handgrip-based body composition equation in grip vs non-grip athletes

Background Body composition assessment in collegiate athletes can be a valuable tool to enhance performance through training and nutrition practices. Due to the limited resources available at many institutions, it is imperative to utilize low-cost methods for such assessments. Nickerson et al. recently developed a BMI-based equation (BMINICKERSON), incorporating handgrip strength as a surrogate for lean mass, which resulted in low error in estimating body fat percentage (BF%) in the general population of adults. However, follow-up research reported reduced accuracy in collegiate athletes, particularly those from non-grip-dominant sports, where handgrip strength may not reflect overall lean mass. Therefore, the aim of the current study was to further evaluate BMINICKERSON while accounting for grip [GR]-dominant athletes vs non-grip [NGR]-dominant athletes.Methods Seventy (n = 70) Division II intercollegiate athletes (n = 37 males, 33 females; 46 NGRs, 24 GRs) were assessed for BF% using BMINICKERSON, bioelectrical impedance analysis (BIA), and seven-site skinfold (SF). Pearson’s correlation analyses were implemented to determine the relationship between each measurement method in both NGR and GR. Furthermore, a grip × measurement method two-way ANOVA with repeated measures on the latter was used to assess the clinical relevance of the observed differences in BF% as estimated by each method between athlete types.Results Pearson’s correlation revealed excellent agreement between BMINICKERSON and both SF and BIA (r = 0.90 and r = 0.94, respectively) in the NGR group. Good to excellent agreement was noted between BMINICKERSON and both SF and BIA (r = 0.75 and r = 0.91, respectively) in the GR group. A significant main effect of measurement method (F = 108.12, p < 0.001) was found for the sample. Subsequent paired samples t-testing revealed a significantly greater BF% estimation using BMINICKERSON (22.35% ± 5.91%) than both SF (t = 12.88, p < 0.001, 17.07% ± 6.85%) and BIA (t = 16.99, p < 0.001, 17.86% ± 5.72%). SF and BIA did not significantly differ (t = 1.99, p = 0.051). No significant main effect of grip or grip × measurement method interaction was observed.Conclusions Although the use of BMINICKERSON in estimating body composition displayed good to excellent agreement with SF and BIA regardless of grip dominance, the clinical relevance of the equation as a measurement tool for athletes remains doubtful. Further research comparing BMINICKERSON to a gold standard body composition method in athletes is warranted.