Effect of Resistive Knee Extension Training on Postural Control Measures in Middle Aged and Elderly Persons.

Abstract

The purpose of the present study was to determine whether knee extension strength gain in middle-aged and elderly persons is associated with improvement in the limits of stability when leaning his/ her body in various directions. The resistance training group (EXT; 4 males, 17 females) completed two bilateral knee extension training sessions, consisting of one set of exercises, per week for 10 weeks. The non-training control group (CONT; 4 males, 3 females) were instructed not to train their legs during the 10-week control period. One set of exercises consisted of 8-12 repetitions of a dynamic resistance exercise until volitional fatigue for knee extension. The initial load for training was set at 70% of the one-repetition maximum (1-RM). The thickness of the rectus femoris (RF) and vastus lateralis (VL) muscles were measured using a B-mode ultrasound apparatus. The postural control measures, obtained using the Balance Master system, included the percentage limits-of-stability (%LOS) and path length (%Path). The 1-RM in EXT was increased significantly by resistance training (p<0.001). In addition, significant differences were observed between the percentage increase of 1-RM in EXT and those in CONT at wk 5 and at wk 10 of resistance training (p<0.001). However, no significant increase in muscle thickness of RF or VL was found in EXT. The %LOS to the rear target in EXT was increased significantly by resistance training (p<0.05-0.01). In addition, the percentage change in %Path was decreased significantly by resistance training (p<0.001). Therefore, strength gain in quadriceps femoris appears to be associated with improvement in the %LOS and %Path for the rear. In conclusion, strength gain in quadriceps femoris is thought to possibly enable accurate movement of the COG farther from the center target towards the rear, suggesting that strength gain has a positive influence on a person's perception of their ability to avoid falls.

Effects of a Physical Activity Intervention Program on Nutritional Status and Health-Related Physical Fitness in Thai Older Adults: Pilot Study

“…Furthermore, there were significant improvements in 8-fit upand-go, which is a demonstration of agility/dynamic balance that is related with lower limb muscle strength (23). In fact, Ryushi et al (24) demonstrated that better balance was due to rises in muscular strength in older adults. Thus, it seems reasonable to believe that these Thai elderly adults significantly improved the performance of tasks dependent on muscle strength (e.g.…”

Training and Detraining Effects on Functional Fitness after a Multicomponent Training in Older Women

“…Probably, these agility/dynamic balance improvements might be related to increased muscular strength observed during the training period. In fact, Ryushi et al [36] demonstrated that better balance was due to rises in muscular strength in older adults. Additionally, specific balance activities used in the present study may possibly have stimulated additional benefits [9] .…”

Comparison Between a Trunk Training Machine and Conventional Exercises For Trunk Extensors and Effect on Stance Weight Distribution of Young Adults: A Pilot Study.

“…Appropriate strength training may have a positive effect on maximal strength (14,15), muscle size (16,17), muscle architecture (18) and the control of muscular contraction force (14)(15)(16)(17)(18)(19)(20). Another function that is often observed to improve with resistance training is postural stability (21,22). In addition to strength exercises, muscle stretching exercises are also used in conventional physical therapy (23).…”