Effects of detraining on knee extensor strength and functional mobility in a group of elderly women.

Long-term detraining results for individuals 75 years and older are needed. The purpose of this study was to assess long-term detraining effects on quadriceps strength and functional mobility in nursing home residents. Ten women (X = 82.8 years) who completed a strength training program were reassessed 1 year later. Clinical methods were used to remeasure dynamic and isometric quadriceps strength and functional mobility. One repetition maximum quadriceps strength declined 68.3% (p < 0.05) from trained values. Isometric strength losses were 29.8% at 90 degrees (p < 0.05), 28.7% at 60 degrees (p < 0.05), and 24.4% at 20 degrees (p < 0.05) of knee flexion 1 year postexercise. Fast-paced walking, self-selected paced walking, and timed up and go speed decreased 28.6% (p < 0.05), 19.5% (p < 0.05), and 54.1% (not significant), respectively, from posttraining. One year vs. baseline, isometric strength decreased 0-14.3%, dynamic strength decreased 48.9%, and functional mobility declined 16.5-20.7% despite an intervening training program. An increased strength loss rate beyond the age of 80 years may be a major factor influencing functional independence.