Effects of exercise on lipid metabolism and musculoskeletal fitness in female athletes.

Aim: This study investigated the effects of intense training on lipid metabolism, bone metabolism and bone mineral density (BMD) in female athletes.

Methods: Sixty-six female subjects participated in this study, age ranging from 18 to 55 years. The sample group included thirty-six athletic subjects and the control group comprised thirty non-athletic individuals. Five athletes competed with national level (5/36) and nine non-athletic subjects (9/30) were postmenopausal women. The assessment items included body composition, radius BMD, calcaneus BMD, lung function, muscular endurance, renal and liver function, bone marker assay and hormone status. All data were analysed, using SPSS 10.0 software, and were presented as mean rank statistical difference, using the Kurskal-Wallis (K-W) test. After that the non-parameter statistics were used. Either K value or P value below 0.05 was considered significant.

Results: Urine deoxypyridinoline/creatinine (Dpd/Cre) levels increased significantly (5.93+/-2.31 vs 6.85+/-1.43, K<0.01), sit-reach (29.30+/-9.48 cm vs 41.31+/-9.43 cm, K<0.001, P<0.001), 1 minute sit-ups with bended knees (1 min sit-ups) (17.60+/-9.34 count vs 30.00+/-10.38 count, K<0.001, P<0.001), and vertical jump (25.27+/-6.63 cm vs 34.69+/-7.99 cm, K<0.001, P<0.001) improved significantly in the athletes group. The athletes group also had a significantly increased level of estriol (E(3)) (0.14+/-0.13 pg/mL vs 0.07+/-0.04 pg/mL, K<0.01, P<0.01), radius BMD (1.37+/-0.49 gm/cm(2) vs 1.19+/-0.40 gm/cm(2), K<0.05) and calcaneus BMD (0.57+/-0.17 gm/cm(2) vs -0.20+/-0.17 gm/cm(2), K<0.01, P<0.05) compared with those of the controls. The high density lipoprotein (HDL) (65.00+/-14.02 mg/dL vs 52.26+/-4.84 mg/dL, K<0.05, P<0.05) was significantly lower in postmenopausal inactive athletes (5/36) than premenopausal active athletes (31/36). On the other hand, low-density lipoprotein (LDL) (98.35+/-23.84 mg/dL vs 131.00+/-21.63 mg/dL, K<0.05, P<0.01), cholesterol (CHO) (164.03+/-27.01 mg/dL vs 193.00+/-23.48 mg/dL, K<0.05, P<0.05), triglyceride (TG) (63.00+/-26.39 mg/dL vs 147.00+/- 87.21 mg/dL, K<0.01), body fat % (BF%) (28.16+/-4.90% vs 34.84+/-4.44%, K<0.05, P<0.001) and body mass index (BMI) (21.98+/-2.98 kg/m(2) vs 26.42+/-5.01 kg/m(2), K<0.05, P<0.001) were significantly higher in postmenopausal inactive athletes (5/36) than premenopausal active athletes (31/36). TG (90.22+/-39.82 mg/dL vs 147.00+/-87.21 mg/dL), CHO (186.44+/-24.90 mg/dL vs 193.00+/-23.48 mg/dL) were higher, but the HDL was significantly lower (62.18+/-10.68 mg/dL vs 52.26+/-4.84 mg/dL, P<0.05) in postmenopausal athletes (5/36) group than in postmenopausal control group (9/30).

Conclusion: Postmenopausal athletes (5/36) who no longer took competing exercises had reduced levels of physical activity, faced increased risk of cardiovascular disease compared to active athletes (31/36) and the postmenopausal controls (9/30). We may thus concluded that long term exercise effectively improves musculoskeletal fitness and prevents BMD loss in female athletes.