Serious adverse events were rare , and no serious events were reported to be directly related to the exercise programme .
This review provides evidence that PRT is an effective intervention for improving physical functioning in  older people , including improving strength and the performance of some simple and complex activities .
BACKGROUND Muscle weakness in old age is associated with physical function decline .
Progressive resistance strength training ( PRT ) exercises are design ed to increase strength .
OBJECTIVES To assess the effects of PRT on older people and identify adverse events .
In vivo human muscle structure and function: adaptations to resistance training in old age.
This study investigated changes in elderly muscle joint angle-torque relation  induced by  resistance training . Older adults were assigned to either training ( n = 9 , age 74.3 + /- 3.5 years ; mean + /-s.d . ) or to control groups ( n = 9 , age 67.1 + /- 2 years ) .  Leg-extension and leg-press exercises were performed three times per week for 14 weeks . Maximal isometric knee extension torque was measured across the knee joint angle range of movement . Vastus lateralis muscle architecture was examined in vivo using ultrasonography . The vastus lateralis muscle fascicle force was estimated from the measured joint torque , enabling construction of the fascicle length-force relation . Electromyographic ( EMG ) activity was measured from representative agonist and antagonist muscles . Training altered the angle-torque relation : ( a ) displacing it by 9 - 31 % towards higher torque values ( P < 0.05 ) ; and ( b ) shifting the optimal angle from 70 deg ( corresponding torque : 121.4 + /- 61 N m ) before to 60 deg ( 134.2 + /- 57.2 N m ; P < 0.05 ) after training . Training also altered the fascicle length-force relation : ( a ) displacing it by 11 - 35 % towards higher force values ; and ( b ) shifting the optimal fascicle length from 83.7 + /- 8 mm ( corresponding force : 847.9 + /- 365.3 N ) before to 93.2 + /- 12.5 mm ( 939.3 + /- 347.8 N ; P < 0.01 ) after training . The upward displacement of the angle-torque relation was mainly due to a training-induced increase in agonist activation , whilst the shift in the optimal angle was associated with changes in muscle-tendon properties
Serious adverse events were rare , and no serious events were reported to be directly related to the exercise programme .
This review provides evidence that PRT is an effective intervention for improving physical functioning in  older people , including improving strength and the performance of some simple and complex activities .
BACKGROUND Muscle weakness in old age is associated with physical function decline .
Progressive resistance strength training ( PRT ) exercises are design ed to increase strength .
OBJECTIVES To assess the effects of PRT on older people and identify adverse events .