This review found that muscle strength , balance , and endurance can be improved by physical activity in people aged 40 - 65 years .
There were bigger effects on muscle strength from programs that used resistance exercises , indicating the need to include a resistance training component if strength enhancement is the goal
QUESTION Can physical activity  in adults aged 40 - 65 years enhance strength and balance and prevent falls ?
The effect of unilateral and bilateral strength training on the bilateral deficit and lean tissue mass in post-menopausal women
Some have observed maximal strength of simultaneous bilateral homologous limb contraction is less than the sum of strengths of right and left limbs contracting alone ; a phenomenon referred to as the bilateral deficit ( BLD ) . There is controversy on whether there is a BLD for all exercises . We assessed whether a BLD occurs across different exercises ( leg press , knee extension , and lat pull-down ) , whether the BLD could be altered with unilateral or bilateral training , and whether unilateral versus bilateral training was more beneficial for increasing lean tissue mass ( LTM ) . Post-menopausal women ( ~57 years ) were r and omized to bilateral ( n=14 ) and unilateral ( n=12 ) training , or non-training control ( n=24 ) groups .  Bilateral training involved seven exercises performed with bilateral contractions ( two sets , 3 days week−1 , 26 weeks ) . Unilateral training involved the same exercises performed with one limb at a time . A BLD was found for leg press and lat pull-down , but not for knee extension . Bilateral training  decreased the BLD ; whereas unilateral training had minimal effect on the BLD . The unilateral-training  group had a greater increase in lower-body LTM compared to the control group ( P<0.05 ) ; however , there were no differences between unilateral and bilateral training groups . Both training groups had greater increases in LTM of the upper- and whole-body compared to the control group . We conclude that the BLD is apparent for some exercises ( i.e. , the leg press and lat pull-down ) but not others ( i.e. , knee extension ) . Bilateral training  reduces the BLD ; whereas unilateral training has minimal effect on the BLD
This review found that muscle strength , balance , and endurance can be improved by physical activity in people aged 40 - 65 years .
There were bigger effects on muscle strength from programs that used resistance exercises , indicating the need to include a resistance training component if strength enhancement is the goal
QUESTION Can physical activity  in adults aged 40 - 65 years enhance strength and balance and prevent falls ?