title: Retraining of a competitive master athlete following traumatic injury: a case study.
abstract: OBJECTIVE
  The purpose of this study was to examine the physiological effects of detraining and retraining in a female master cyclist (age, 49.5 yr; wt, 54 kg) following a surgically-treated clavicular fracture complicated by brachial plexus impingement.
  
  
  METHODS
  Variables associated with cycling performance, including VO2max, lactate threshold (LT), power output at a blood lactate concentration of 4 mM (LT(4 mM)), peak power output (PPO), muscular resistance to fatigue measured by a timed ride to exhaustion at 110% of peak power output (PPO110), and body composition (hydrostatic weight) were assessed 2 d before the injury when the subject was at the peak of her competitive season, and at days 0, 14, 28, 42, and 77 of the retraining period. Retraining gradually increased from 3 h x wk(-1) to 9-10 h x wk(-1) with an increase in intensity from approximately 70 to 95+% of HRmax.
  
  
  RESULTS
  Detraining resulted in a 25.7% decrease in VO2max and a 16.7% and 18.9% decrease in LT and LT(4 mM), respectively, while peak power output and PPO110 declined 18.2% and 16.6%, respectively. Body fat percent increased 2.1 percentage points, while fat-free mass decreased nearly 2 kg. After 2 wk of retraining, all variables except the LT and LT(4 mM) had improved considerably; however, VO2max was still 14.8% lower and PPO and PPO110 were 12.7% and 5.7% lower than preinjury values. By the 11th week of retraining, all variables had essentially returned to their preinjury values.
  
  
  CONCLUSIONS
  These data demonstrate a pattern of retraining in which aerobic power steadily improved over 6 wk, while measures of lactate threshold did not change until the fourth week of retraining when the intensity of training was markedly increased. Additional data are needed to determine whether this pattern of retraining would be consistent in other master athletes.
authors.affiliation: Department of Exercise & Nutritional Sciences, San Diego State University, and San Diego Sports Medicine and Family Health Center, CA 92182-0171, USA. jnichols@mail.sdsu.edu
authors.forename: J F
authors.initials: JF
authors.lastname: Nichols
authors.forename: D
authors.initials: D
authors.lastname: Robinson
authors.forename: D
authors.initials: D
authors.lastname: Douglass
authors.forename: J
authors.initials: J
authors.lastname: Anthony
mesh_terms: D001642:Bicycling; D020516:Brachial Plexus Neuropathies / Q000209:etiology / Q000473:pathology; D002968:Clavicle / Q000293:injuries*; D005081:Exercise Therapy; D005260:Female; D005596:Fractures, Closed / Q000150:complications / Q000473:pathology* / Q000628:therapy; D006801:Humans; D008875:Middle Aged; D010809:Physical Fitness