Einfluss unterschiedlicher körperlicher Belastung in Beruf und Freizeit auf die Entwicklung der Peak Bone Mass junger Erwachsener

Zusammenfassung

Einleitung und Ziel der Studie

Nur wenige Untersuchungen erfassen den Effekt körperlicher Aktivität oder körperlichen Trainings auf die Entwicklung der Peak Bone Mass (PBM) bei jungen Erwachsenen. Ziel der Untersuchung war es, den Einfluss beruflich bedingter hoher bzw. niedriger körperlicher Belastung auf die Entwicklung der Knochendichte (BMD) in dieser Lebensphase zu erfassen.

Patienten, Material und Methoden

61 körperlich inaktive Zahnmedizin- (ZM: 21 ± 3 J.) vs. 53 körperlich hochaktive Sportlehramtsstudent( inn)en (SLS: 20 ± 2 J.) wurden studienbegleitend untersucht. Die BMD für Gesamtkörper, LWS und Hüfte wurde mittels DXA erfasst.

Ergebnisse

Nach 5-jährigem Untersuchungszeitraum stieg in der Gruppe der SLS die BMD an allen Regionen signifikant an, während diese bei den ZM stagnierte oder signifikant abnahm. Auch nach Adjustierung auf die unterschiedlichen basalen BMD-Daten der SLS vs. der ZM-Gruppe blieben die korrespondierenden Zwischengruppen-Unterschiede der BMD-Veränderung signifikant. Unterschiedliche körperliche Belastung im jungen Erwachsenenalter zeigt also auch bei weit-gehend realisierter PBM signifikanten Einfluss auf die Knochendichte.

Fazit

Somit belegt die vorliegende Studie, dass adäquates Sporttreiben im jungen Erwachsenenalter ein wichtiger Faktor der “Knochengesundheit” darstellt.

Summary

Introduction and aim of the study

There is some evidence that the risk of osteoporosisrelated fractures may be reduced by maximizing Peak Bone Mass (PBM) in childhood and adolescence. In this context, physical activity or exercise is a highly relevant factor for increasing Bone Mineral Density (BMD) in this period of skeletal maturation. However, only few studies have determined the effect of physical activity or physical exercise on BMD in the period around PBM. Thus, the aim of this article was to determine the effect of different grades of physical activity and exercise arising from clearly defined occupational effects during young adulthood.

Patients, material und methods

Sixty-one male and female dentist-students (DES: 21 ± 3 years) with known high occupational stress and low physical activity levels and 53 male and female sport students (SPS: 20 ± 2 years) were accompanied over the course (4.8 ± 0.5 years) of their academic career. BMD at the total body (TB), lumbar spine (LS) and hip were determined using DXA-technique at study start and during the last semester of the study period.

Results

Based on comparable data at baseline, occupational and leisure time physical activity increased non-significantly in both groups (SPS: p = 0,096 vs. DES: p = 0,058) with no relevant differences between the groups. This parameter, which reflects significantly higher total amount of exercise compared with the DES-group at baseline, increased significantly in the SPS group. A significant decrease was assessed for the DES group (139 ± 104 to 92 ± 77 min/week). Independent of gender, BMD of the SPS increased significantly (p ≤ 0.007) at all skeletal sites assessed (TB: 1.8 ± 2.8 %; LS: 2.4 ± 3.9 %; hip: 1.6 ± 3.5 %) while BMD of the DES remained unchanged at TB (0.5 ± 1.9 %, p = 0.092) and LS (–0.6 ± 4.4 %, p = 0.432) and decreased significantly at the hip (–1.9 ± 4.3 %, p = 0.010). BMD changes at all skeletal sites differ significantly between SPS and DES (p ≤ 0.017). Results remained unchanged when adjusting for baseline BMD values that differs (p = 0.030 to p = 0.082) in favor of the SPS group.

Conclusion

Significant changes of exercise levels caused by occupational factors during the period of PBM significantly affected skeletal maturation and maintenance of PBM during young adulthood. Occupational factors that generally decrease physical activity and/or exercise in young adults are however, the rule in our sedentary society. Compensation through exercise either individually based during leisure-time or provided by the employer as company-facilitated sports activity is thus highly relevant for bone health of young adults.

Schlüsselwörter

Körperliche Inaktivität - Sporttreiben - Knochendichte - Peak Bone Mass - Tätigkeit

Keywords

Physical activity - exercise - Bone Mineral Density - Peak Bone Mass - occupation

• Literatur

• 1 Bielemann RM. et al. Physical activity during life course and bone mass: a systematic review of methods and findings from cohort studies with young adults. BMC musculoskeletal disorders 2013; 14: 77.
• 2 Herrmann A. et al. Einfluss von körperlicher Aktivität und Sporttreiben auf die Knochengesundheit im Lebensalter. Bundesgesundheitsblatt Gesundheitsforschung Gesundheitsschutz 2012; 55 (01) 35-54.
• 3 Pitukcheewanont P. et al. Physical activity and bone health in children and adolescents. Pediatric endocrinology reviews: PER 2010; 07 (03) 275-282.
• 4 Baxter-Jones AD. et al. Bone mineral accrual from 8 to 30 years of age: an estimation of peak bone mass. J Bone Miner Res 2011; 26 (08) 1729-1739.
• 5 Almstedt HC. et al. Changes in Bone Mineral Density in Response to 24 Weeks of Resistance Training in College-Age Men and Women. J Strength Cond Res 2011; 25 (04) 1098-1103.
• 6 Casez JP. et al. Bone mass at lumbar spine and tibia in young males – impact of physical fitness, exercise, and anthropometric parameters: a prospective study in a cohort of military recruits. Bone 1995; 17 (03) 211-219.
• 7 Cohen B. et al. Effect of exercise training programme on bone mineral density in novice college rowers. Br J Sports Med 1995; 29 (02) 85-88.
• 8 Leichter I. et al. Gain in mass density of bone following strenguous physical activity. Journal of Orthopaedic Research 1989; 07: 86-90.
• 9 Ryan AS. et al. Regional bone mineral density after resistive training in young and older men and women. Scand J Med Sci Sports 2004; 14 (01) 16-23.
• 10 Bennell KL. et al. Bone mass and bone turnover in power athletes, endurance athletes, and controls: a 12-month longitudinal study. Bone 1997; 20 (05) 477-484.
• 11 Carbuhn AF. et al. Sport and training influence bone and body composition in women collegiate athletes. J Strength Cond Res 2010; 24 (07) 1710-1717.
• 12 Chilibeck PD. et al. Twenty weeks of weight training increases lean tissue mass but not bone mineral mass or density in healthy, active young women. Can J Physiol Pharmacol 1996; 74 (10) 1180-1185.
• 13 Eickhoff J. et al. The effect of a one-year strength training program on bone mineral density in premenopausal women. J Bone Miner Res 1993; 08 (Suppl. 01) S332.
• 14 Kato T. et al. Effect of low-repetition jump training on bone mineral density in young women. J Appl Physiol 2006; 100 (03) 839-843.
• 15 Schroeder ET. et al. Musculoskeletal adaptations to 16 weeks of eccentric progressive resistance training in young women. J Strength Cond Res 2004; 18 (02) 227-235.
• 16 Snow CM. et al. Bone gains and losses follow seasonal training and detraining in gymnasts. Calcif Tissue Int 2001; 69 (01) 7-12.
• 17 Snow-Harter C. et al. Effects of resistance and endurance exercise on bone mineral status of young women: a randomized exercise intervention trial. J Bone Miner Res 1992; 07: 761-769.
• 18 Taaffe DR. et al. High-impact exercise promotes bone gain in well-trained female athletes. J Bone Miner Res 1997; 12 (02) 255-260.
• 19 Kemmler W, von Stengel S. Exercise and osteoporosis-related fractures: Perspectives and recommendations of the sports and exercise scientist. Physician and Sportmedicine 2011; 39 (01) 142-157.
• 20 Rada RE, Johnson-Leong C. Stress, burnout, anxiety and depression among dentists. J Am Dent Assoc 2004; 135 (06) 788-794.
• 21 O’Shea RM. et al. Sources of dentists’ stress. J Am Dent Assoc 1984; 109 (01) 48-51.
• 22 Hologic I. QDR 4500a – Users Guide. Manual. Waltham: Hologic Inc; 1996
• 23 Kemmler W. et al. The effect of habitual physical activity, non-athletic exercise, muscle strength, and VO2max on bone mineral density is rather low in early postmenopausal osteopenic women. J Musculoskelet Neuronal Interact 2004; 04 (03) 325-334.
• 24 Kemmler W. et al. Bone status in elite male runners. Eur J Appl Physiol 2006; 96 (01) 78-85.
• 25 Kemmler W. et al. Effect of exercise, body composition, and nutritional intake on bone parameters in male elite rock climbers. Int J Sports Med 2006; 27 (08) 653-659.
• 26 Cohen J. Statistical power analysis for the behavioral sciences. 2nd ed. Hillsdale, NJ: Lawrence Earlbaum Associate; 1988
• 27 Schoeffl I. et al. Physical activity, strength and VO2max have no significant influence on bone parameters in elderly women. J Musculoskelet Neuronal Interact 2008; 08 (04) 363-374.
• 28 Meyer U. et al. Effect of a general school-based physical activity intervention on bone mineral content and density: a cluster-randomized controlled trial. Bone 2011; 48 (04) 792-797.
• 29 Kramer J. et al. [Epidemiological study on the dimension of vitamin D deficiency in North Germany]. Dtsch Med Wochenschr 2014; 139 (10) 470-475.
• 30 Witzke KA, Snow CM. Effects of plyometric jump training on bone mass in adolescent girls. Med Sci Sports Exerc 2000; 32 (06) 1051-1057.
• 31 Heublein U. et al. Die Entwicklung der Studienabbruchquote an den deutschen Hochschulen. Hannover: 2008
• 32 Moher D. et al. CONSORT 2010 explanation and elaboration: updated guidelines for reporting parallel group randomised trials. BMJ 2010; 340: c869.