The Relationship Between BMI And Skinfold Measurements In High-intensity Functional Training Athletes

Introduction: Body Composition (BC) is especially important for High-Intensity Functional Training (HIFT) athletes to enhance their performance. A low fat mass and high muscle mass is advantageous for the gymnastics skills, cardiovascular training, and weightlifting HIFT athletes use as part of their training regimen. Purpose: The aim of this study was to determine if a correlation exists regarding Skinfold (SKF) testing and Body Mass Index (BMI) in HIFT athletes. Methods: Participants (N = 38) were gathered from two HIFT gyms that were recruited through convenience sampling. At each gym site, participants consented and responded to demographic questions. The researcher then recorded the participant’s height, weight, and 7-siteSKF. Data were analyzed through Statistical Product and Service Solutions (SPSS) software. The relationship between Percent Body Fat (%BF) and BMI was investigated with Pearson’scorrelation coefficients by sex (male, n = 19, Age, M = 38.74 ± 12.12; female, n = 19, Age, M = 34.79 ± 8.70) as well as the whole group (BMI, M = 27.01, SD = 3.39 ; %BF, M = 17.74,SD = 5.16). Results: A moderate, linear relationship was present among female athletes (r = .69,p < .001) though not significant among male athletes (r = .43, p = .064). However, there was no significant correlation present between the variables when examining the overall group (r = .01,p = .946). Conclusions: These results indicate that %BF may be more correlated with BMI in female HIFT athletes. The lack of correlation between %BF and BMI of male HIFT athletes and HIFT athletes as a whole should caution practitioners in BMIs use in estimating BC. Further study might be necessary to understand why female HIFT athletes %BF and BMI are correlated when compared to males who were not correlated. Further research should also examine the relationship between BMI and other methods of BC assessment in HIFT athletes.