Physical activity, muscle function, falls and fractures

Abstract

Study design: A thematic review.
Objectives: To evaluate if physical activity enhances muscle strength, improves balance, and reduces the fall
frequency and the fracture incidence.
Background: One of the major medical problems of today is the increasing incidence of fragility fractures.
Muscle strength and fall is one of the major determinants of a fracture. If physical activity could increase
muscle strength, improve balance and reduce the fall frequency, then training could be recommended as
prevention for fractures.
Methods: The review used Medline (Pub Med) and the search words exercise, physical activity, muscle
strength, balance, falls, fractures. Randomized controlled trials (RCT) were predominantly included,
although this not is a systematic review.
Results: The evidence that physical activity modifies the risk factors for fall is compelling, although RCT with
fractures as end point are lacking. Physical activity is associated with improved muscle strength, co-ordination
and balance. Physical training increases muscle strength also in octogenarians by up to 200%, i.e. a much
more pronounced effect than the corresponding increase in muscle volume or bone mass. There is also
evidence that physical activity decreases the actual number of falls. Observational cohort and case-control
studies imply that physical activity is associated with reduced hip fracture risk. If exercise reduces the number
of vertebral fractures and other fragility fractures are less evaluated.
Conclusions: Physical activity in older ages can be recommended to improve muscle strength and balance, to
reduce the risk to fall and fractures, although the highest level of evidence - RCT with fracture as endpoint -
is lacking.