Adaptations To Bone, Strength, Power, And Body Composition In Women With Varying Training Protocols.

Abstract

Exercise mode selected can impact the adaptations generated. PURPOSE: To determine the impact of exercise mode on bone health, strength, power, and body composition. METHODS: Thirty-three women (41±5yrs) were randomly assigned either an Aerobic (n=9; AER), or Machine (n=13; M) or Functional (n=11; F) resistance based training protocol. Two, one hr training sessions per week were completed for 12-months. Bone mineral density (BMD) for the lumbar, left hip, and right hip (L; LH; RH) were assessed at baseline (BL) and 12-months (M12) via DEXA. Osteocalcin (OST), upper and lower body strength (UBS, LBS), upper and lower body power (UBP, LBP), and body weight (WT) and body composition (%BF), were assessed at BL, 6-month (M6), M12. 3x3 Factorial ANOVAs with repeated measures were used to determine if differences or interactions existed between specific training groups (AER; M; F) for WT, %BF, UBS, UBP, LBS, LBP, and OST. 2x3 factorial ANOVAs with repeated measures were conducted for BMD: L, LH, and RH. RESULTS: No significant interactions or main effects for group or time (p>.05) were observed for WT, %BF, OST, or BMD variables. No significant interaction or main effect (p>.05) for group was found for UBS or UBP but a significant difference was found for time. BL UBS (28.74±1.23kg) and UBP (348.09±9.23cm) were significantly lower than M6 (UBS: 33.24±1.37kg, UBP: 379.21±10.53cm) and M12 (UBS: 34.90±1.38kg, UBP: 393.30±9.76cm). UBS and UBP were significantly lower at M6 compared to M12. Significant interactions were found for LBS and LBP. For the F and M groups, LBS and LBP was significantly less at BL (F LBS: 68.18±6.61kg, F LBP: 18.27±2.03cm, M LBS: 71.10±8.29kg, M LBP: 16.99±2.03cm) than M6 (F LBS: 130.79±6.36kg, F LBP; 24.46±1.99cm, M LBS: 100.69±7.97kg, M LBP: 21.58±1.99cm) and M12 (F LBS: 123.54±7.84kg, F LBP: 22.15±1.82cm, M LBS: 100.47±9.83kg, M LBP: 22.97±1.82cm), but no significant differences existed from M6 to M12. No significant differences (p>.05) existed in LBS or LBP across time for AER. No significant differences (p>.05) existed in LBS between the 3 training groups at BL; however F had significantly greater LBS compared to AER (p=.00) and M (p=.01) at M6 and AER (p=.01) at M12. CONCLUSION: Regardless of mode, exercise maintained BMD and body composition and generated improvements in strength and power in women.