A comparative study of bone mineral density in females doing weight bearing exercise and non-weight bearing exercise using dual energy x-ray absorptiometry
Osteoporosis is reported to effect 44 million adults, of whom 80% are women. Exercise appears to influence the osteogenic response and can lead to higher values of Bone mineral density. A minimum research is done on bone mineral density using dual energy x-ray absorptiometry (DEXA) in India. Weight bearing exercises seem to have a better effect than nonweight bearing exercises.
Aim: our aim of this retrospective cohort study is to confirm that weight bearing exercise is beneficial to bone mineral density than non weight bearing exercise.
Materials and Methods: A total of 50 healthy active women (n=50) doing weight bearing exercises like tennis playing and gym weight workouts for atleast one hour, for 5 days a week were taken. (Group A). A total of 50 healthy walkers with minimum walking of one hour for 5 days a week were taken (Group B). Dual-energy X-ray absorptiometry (DXA) was done to assess the bone mineral density in all the participants. Bone mineral density (BMD) in gram per square centimeter of lumbar spine (L1-L4), surgical neck of right humerus and total body BMD was assessed with a hologic QDR-1000/W pencil-beam bone densitometer, using the spine scan mode. Statistical analysis was done using Statistical package for the social sciences (SPSS software, version 13.0). Analysis of covariance was used to determine whether there were significant differences between groups in bone mineral density, adusting height and weight.
Results: The Total body BMD in gm/cm2 in group A is 1.172+ 0.034 and the Total body BMD in gm/cm2 in group B is 1.078+0.053. (P value < 0.001) Lumbar spine BMD in gm/cm2 in Group A is 1.216+0.122 and the Lumbar spine BMD in gm/cm2 in Group B is 0.968+/-0.128. (P value <0.05) Humerus BMD in gm/cm2 in group A is 1.22+0.043 and the BMD in gm/cm2 in group B is 1.110+0.066. (P value < 0.001).
Conclusion: since, the Total body BMD, Lumbar spine BMD, Humerus BMD in gm/cm2 is higher in subjects doing weight bearing exercise when compared to the subjects doing non weight bearing exercise. We confirm that weight bearing exercises are beneficial to bones when compared to nonweight bearing exercises.
Keywords: Bone mineral density, Dual energy x-ray absorptiometry, Osteoporosis.