title: Physical activity, exercise, and sarcopenia - future challenges.
abstract: BACKGROUND
  Numerous studies have demonstrated that the etiology of sarcopenia is multi-causal and very complex process. The degradation of muscle mass leads to a loss of strength, later on to a decreased functional status, impaired mobility, a higher risk of falls, and eventually an increased risk of mortality. Present guidelines state that physical inactivity or a decreased physical activity level is a part of the underlying mechanisms of sarcopenia and therefore physical activity can be seen as an important factor to reverse or modify the development of sarcopenia.
  
  
  OBJECTIVE
  Results in the area of physical activity and aging have not always been homogeneous. The inconsistent findings in this research area are related to the different understanding of terms and underlying constructs along with different population, type of intervention, or measurement methods. These aspects will be discussed in the paper. With regard to the formulated future role of physical activity this article will discuss in addition different barriers and challenges in the prevention and treatment of sarcopenia. A multitude of studies shows that structured exercise programs including progressive resistance or power training have positive effects on sarcopenia and sarcopenia-related outcomes but less or inconclusive information is available for the transfer to functional outcomes.
  
  
  CONCLUSIONS
  Both physical activities and exercise have shown to decrease risk of sarcopenia and onset of functional limitations in older persons. Unfortunately the cohort of older persons is the one with the highest percentage of individuals classified as inactive or sedentary. Therefore motivating older persons to increase their physical activity level as well as providing safe access to exercise programs seems to be a mandatory task.
authors.affiliation: Institute of Sport Science and Sports, Friedrich-Alexander-University Erlangen-Nürnberg, Erlangen, Germany. ellen.freiberger@sport.uni-erlangen.de
authors.forename: Ellen
authors.initials: E
authors.lastname: Freiberger
authors.forename: Cornel
authors.initials: C
authors.lastname: Sieber
authors.forename: Klaus
authors.initials: K
authors.lastname: Pfeifer
mesh_terms: D000368:Aged; D015444:Exercise / Q000502:physiology*; D006801:Humans; D009043:Motor Activity / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology; D018482:Muscle, Skeletal / Q000503:physiopathology*; D055070:Resistance Training; D012307:Risk Factors; D055948:Sarcopenia / Q000503:physiopathology* / Q000517:prevention & control* / Q000534:rehabilitation; D057185:Sedentary Behavior