title: Physical activity, muscle function, falls and fractures.
abstract: METHODS
  A thematic review.
  
  
  OBJECTIVE
  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.
authors.affiliation: Department of Orthopaedics and Clinical and Molecular Osteoporosis Research Unit, Department of Clinical Sciences, Malmö University Hospital, Lund University, Sweden.
authors.forename: Magnus K
authors.initials: MK
authors.lastname: Karlsson
authors.forename: Anders
authors.initials: A
authors.lastname: Nordqvist
authors.forename: Caroline
authors.initials: C
authors.lastname: Karlsson