Isokinetics and Exercise Science 20 (2012) 221–227 221 DOI 10.3233/IES-2012-0463 IOS Press Long-term basketball playing enhances bone mass and isokinetic muscle strength Haithem Rebai a , Nidhal Zarrouk b,∗ , Sameh Ghroubi c , Mouna Sellami c , Fatma Ayedi d , Sofien Baklouti c , Mohamed Habib Elleuch c and Mohamed Elleuch c a Unit´ e de Recherche, “Adaptations Cardio-circulatoires, Respiratoires, M´ etaboliques et Hormonales”, Facult´ e de M´ edecine Ibn El Jazzar, Sousse, Tunisia b Unit´ e de Recherche, “Neurophysiologie de la Vigilance, de l’Attention et des Performances” (99/UR/08-23), Service d’Explorations Fonctionnelles du Syst` eme Nerveux, CHU Sahloul, Sousse, Tunisia c Unit´ e de Recherche, “Les Pathologies de l’Appareil Locomoteur”, 04/UR/08-07, Service de M´ edecine Physique et de R´ eadaptation, CHU Habib Bourguiba, Sfax, Tunisia d Service de Biochimie, CHU Habib Bourguiba, Sfax, Tunisia Abstract. Aim: To evaluate bone mass in female basketball players and the relationship between bone mineral density (BMD) and isokinetic muscle strength. Methods: We investigated 29 female basketball players, age 21.9 ± 9.1 years, training for about 6–8 hours per week. The reference group consisted of 22 non-active female, age 21.4 ± 1.5 years. BMD was measured using dual-energy-X-ray absorptiometry in total body, lumbar spine, the whole femur and humerus. Isokinetic peak torque of the quadriceps and hamstring muscles were measured at 60 and 180 ◦ /s. Osteocalcin (OC) and cross-linked C-telopeptide (CTX) were measured by radioimmunoassay and electrochimiluminescence, respectively. Results: Compared to the controls, the basketball group had significantly (P< 0.001) a higher BMD in the total body (11.6%), the lumbar spine (9.83%), the dominant femur (16.8%), the non-dominant femur (15.8%) and the dominant humerus (8.47%). The female basketball players had also significantly higher peak torques at both isokinetic velocities (60 and 180 ◦ /s) and for both lower limbs. All muscle peak torque measured for the female basketball players were significantly correlated with correspondent leg BMD and for both velocities tested. However, no significant correlations were noted for the control group. Values of formation (OC) and resorption (CTX) markers were significantly higher in the athletic females (P< 0.01 and P< 0.05, respectively). Conclusion: Our results show clearly that practice of basketball is associated with the improvement of bone mass. In addition, the most important finding of our study is that isokinetic muscle strength seems to be correlated with correspondent BMD in female basketball players. Keywords: Bone mass, sports activities, female, muscle, isokinetic 1. Introduction Peak bone mass attained by young women during adolescence is an important factor in preventing os- teoporosis and associated fractures in adulthood [1,2]. Several important factors may affect bone acquisition. This process is controlled by complex and selective ∗ Corresponding author: Nidhal Zarrouk, Institut Sup´ erieur de Sport et de l’Education Physique de Sfax Route de l’A´ eroport, Km 3.5, BP 384, Sfax 3000, Tunisia. E-mail: nidhal.zarrouk@yahoo. com. genetic and environmental factors including hormone status, nutrition and physical activity [3,4]. The role of physical activity in the formation and preservation of the bone mineral density (BMD) have been well documented in the literature. Several cross section- al studies have demonstrated that athletes involved in weight-bearing activities (i.e., football, volleyball etc.) increase more BMD than general population [5–7]. In fact, recently it has been shown that long-term recreational football practice [8,9] and r´ esistance train- ing [10] improve muscle strength and bone mass den- sity in premenopausal women. In addition, others re- ISSN 0959-3020/12/$27.50  2012 – IOS Press and the authors. All rights reserved AUTHOR COPY