The effects of whole-body vibration training on knee function and physical performance of middle-aged and elderly woman with knee osteoarthritis and chronic knee pain / 体力科学

The purpose of this study was to elucidate the effects of whole-body vibration training (WBVT) on knee function and physical performance in middle-aged and older Japanese women who suffered from knee osteoarthritis (OA) and knee pain. Thirty-eight middle-aged and older Japanese women (aged 50-73 years) with knee OA and knee pain were divided into two groups: (1) a WBVT group (n = 29) engaging in WBVT 3 times a week for 8 weeks, and (2) a control group (C group, n = 9) performing exercises at home. The WBVT program consisted of a warm-up, strength training mainly of the quadriceps and their surrounding muscles and cool-down exercises. In the WBVT group, there were no dropouts, and there were significant improvements in the physical function (Cohen’s <i>d</i> = 0.28) and total score (Cohen’s <i>d</i> = 0.25) of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). There were also statistically significant improvements in all lower-extremity function tests (5-times sit-to-stand, timed up and go, standing time from a long sitting position, sit and reach, 4-way choice reaction time; Cohen’s <i>d</i> = 0.34-1.24). The item that changed significantly in the C group, however, was only the sit and reach (Cohen’s <i>d</i> = 0.52). In addition, all items in the Japanese Orthopaedic Association Score (JOA score) improved significantly (Cohen’s <i>d</i> = 0.63-0.67) in the WBVT group. In conclusion, the 8-week WBVT program can safely improve knee function and physical performance in middle-aged and older Japanese women who suffer from knee OA and knee pain.

THE RELATIONSHIP BETWEEN GROUND REACTION FORCE IN A SIT-TO-STAND MOVEMENT AND PHYSICAL FUNCTIONING, HISTORY OF FALLS, FEAR OF FALLING, AND MOBILITY LIMITATIONS IN COMMUNITY-DWELLING OLDER ADULTS / 体力科学

The vertical ground reaction force (GRF) parameters in a sit-to-stand movement are useful for measuring lower-limb muscle strength and power in older adults. The purpose of this study was to examine which GRF parameters would be more strongly associated with a person's physical functioning, history of falls, fear of falling and mobility limitations, all of which are known to be related to lower-limb muscle strength and power. We performed cross-sectional analyses on 363 community-dwelling older adults, which included 160 men and 203 women, aged 65-85 years (73.4 ± 5.3 years). Five parameters were measured: peak reaction force, two rate of force development and two time-related parameters. Their rate of force development was relatively higher correlated with results from timed “up and go” tests, standing times from a long sitting position and 4-way choice reaction times (partial r = -0.37 ∼ -0.52); these tests were accompanied with a dynamic movement of lower-limb; than their peak reaction force and time-related parameters. The rate of force development were poorer in subjects reporting falls, a fear of falling or a mobility limitation compared with those reporting no falls, fear of falling or mobility limitation. These results suggest that measuring the rate of force development in a sit-to-stand movement provide a better assessment of lower-limb muscle strength and power.