Investigation of the relationship of muscle strength and foot posture with balance in elderly and young individuals

Background and Aim: The aim of this study was to investigate the changes in muscle strength, foot posture index and balance in young adults and elderly and to examine the relationship between muscle strength and foot posture index and balance. Material and Methods: In study, young adult group included 52 volunteers from Trakya University, Institute of Health Science, Physiotherapy and Rehabilitation students, elderly group included 53 volunteers residing in Şarköy and its villages. In addition to demographic information, fall and disease history of all participants, foot posture assessed with Foot Posture Index (FPI-6), muscle strength with Handgrip Strength (HGS), static balance with Single Leg Stance Test (SLST – RIGHT and LEFT), dynamic balance with Modified Functional Reach Test (MFRT). Results: The average age of the young group was 21,83 ± 1,823 and elderly group was 69,04 ± 5,313. No differences found between the groups in terms of gender (p=0,680), but statistical differences were found in weight, height and body mass index (p<0,001, p=0,006, p<0,001). In comparison between groups, statistically meaningful difference were found in HGSRIGHT and HGSLEFT (p=0,007, p=0,040), SLSTRIGHT and SLSTLEFT (p<0,001, p<0,001), all MFRT assessments (all p<0,001). No differences found between groups in left and right Foot Posture Index (p>0.05). In the young group, positive correlations were found between HGSRIGHT with MFRTFRONT and MFRTRIGHT (r=0,429, p=0,002; r=0,354, p=0,010). Negative correlations were found between FPI-6RIGHT with MFRTRIGHT and MFRTLEFT (r=-0,320, p=0,021; r=-0,302, p=0,030). In the elderly group, moderate positive correlations were found between HGSRIGHT with SLSTRIGHT, SLSTLEFT and MFRTFRONT (r=0,550, p<0,001; r=0,529, p=<0,001; r=0,596, p<0,001), and weak correlations were found with MFRTBACK, MFRTRIGHT and MFRTLEFT (r=0,377, p=0,005; r=0,450, p=0,00; r=0,430, p=0,001). In the elderly group, weak negative correlations were found between foot posture with SLST on both sides (rho=-0,299, p=0,030; rho=-0,330, p=0,016).viii Conclusion: Lower muscle strength and balance were seen in the elderly compared to young while no difference were found in foot posture. There was weak correlations between muscle strength and balance in the young group while stronger correlations between both static and dynamic balance in the elderly group. Foot posture is associated with static balance in the elderly and dynamic balance in the young.