title: No effect of short-term amino acid supplementation on variables related to skeletal muscle damage in 100 km ultra-runners - a randomized controlled trial.
abstract: BACKGROUND
  The purpose of this study was to investigate the effect of short-term supplementation of amino acids before and during a 100 km ultra-marathon on variables of skeletal muscle damage and muscle soreness. We hypothesized that the supplementation of amino acids before and during an ultra-marathon would lead to a reduction in the variables of skeletal muscle damage, a decrease in muscle soreness and an improved performance.
  
  
  METHODS
  Twenty-eight experienced male ultra-runners were divided into two groups, one with amino acid supplementation and the other as a control group. The amino acid group was supplemented a total of 52.5 g of an amino acid concentrate before and during the 100 km ultra-marathon. Pre- and post-race, creatine kinase, urea and myoglobin were determined. At the same time, the athletes were asked for subjective feelings of muscle soreness.
  
  
  RESULTS
  Race time was not different between the groups when controlled for personal best time in a 100 km ultra-marathon. The increases in creatine kinase, urea and myoglobin were not different in both groups. Subjective feelings of skeletal muscle soreness were not different between the groups.
  
  
  CONCLUSIONS
  We concluded that short-term supplementation of amino acids before and during a 100 km ultra-marathon had no effect on variables of skeletal muscle damage and muscle soreness.
authors.affiliation: Gesundheitszentrum St, Gallen, St, Gallen, Switzerland. beat.knechtle@hispeed.ch.
authors.forename: Beat
authors.initials: B
authors.lastname: Knechtle
authors.forename: Patrizia
authors.initials: P
authors.lastname: Knechtle
authors.forename: Claudia
authors.initials: C
authors.lastname: Mrazek
authors.forename: Oliver
authors.initials: O
authors.lastname: Senn
authors.forename: Thomas
authors.initials: T
authors.lastname: Rosemann
authors.forename: Reinhard
authors.initials: R
authors.lastname: Imoberdorf
authors.forename: Peter
authors.initials: P
authors.lastname: Ballmer