Skeletal Adaptations After 16-Weeks of High Intensity Functional Training: 620 Board #1 June 1, 1: 00 PM - 3: 00 PM

PURPOSE: To examine if gender played a role in skeletal mass adaptations in active adults after 16-weeks of HIFT. METHODS: Nine men (34.2 ± 9.12 years, 1.78 ± 0.05 m, 91.5 ± 17.7 kg) and 17 women (36.3 ± 7.84 years, 1.63 ± 0.07 m, 68.5 ± 12.8 kg) with CrossFit™ experience completed 16-weeks (2-5 sessions/wk) of HIFT. Within two weeks prior to training, pre-testing (PRE) measures of bone mineral density (BMD) and bone mineral content (BMC) were measured using Dual-Energy X-Ray Absorptiometry (DXA). Strength was assessed via a five-repetition maximal front squat (5RM). Post-testing (POST) was completed following 16-weeks of training. RESULTS: Repeated measures analysis of variance did not reveal any significant interactions between the measures. Paired-samples t-tests showed a significant (p \u3c 0.001) decrease in BMD (PRE: 1.24 ± 0.16 g/cm2, POST: 1.09 ± 0.27 g/cm2), an increase in BMC (PRE: 2,855.7 ± 610.68 g, POST: 2,869.2 ± 600.44 g) and an increase in strength (PRE: 66.02 ± 21.52 Kg, POST: 74.43 ± 22.16 Kg) for the entire group. CONCLUSIONS: It appears that a 16-week HIFT program is a suitable exercise modality to increase strength and BMC. However, we believe the length of our study may not be suitable to positively influence BMD. Future studies should consider longer interventions and controlling for total work volume