title: Eccentric endurance exercise economically improves metabolic and inflammatory risk factors.
abstract: BACKGROUND
  Exercise is a cornerstone of cardiovascular prevention. Because many individuals are not willing or not able to perform regular exercise, new methods of exercise (like eccentric exercise) are necessary. Eccentric endurance exercise is supposed to be less strenuous than concentric exercise but its effects on glucose and lipid metabolism in relation to energy expenditure are unclear.
  
  
  METHODS
  We randomly allocated 45 healthy sedentary individuals to one of two groups, each hiking upwards or downwards for 2 months, with a crossover for a further 2 months; for the opposite way, a cable car was used. The difference in altitude was 540 metres; the distance was covered between three and five times a week. Energy expenditure was assessed for each hiking period.
  
  
  RESULTS
  Both eccentric and concentric endurance exercise improved glucose tolerance vs. baseline (by 4.1%, p = 0.136; 6.2%, p = 0.023, respectively). Of note, adjustment for energy expenditure per exercise unit (127 ± 22 kcal/unit with eccentric and 442 ± 78 kcal/unit with concentric exercise) revealed a significantly greater improvement of glucose tolerance per kilocalorie spent by eccentric than by concentric exercise (4-times more economical; 0.1123 mg h/dl/kcal vs. 0.0245 mg h/dl/kcal; p = 0.038). Also the decrease of low-density lipoprotein (LDL) cholesterol per kilocalorie spent was significantly stronger with eccentric exercise (0.0982 mg/dl/kcal vs. 0.0346 mg/dl/kcal, p = 0.014). Serum levels of C-reactive protein and creatine kinase activity were reduced in both groups.
  
  
  CONCLUSIONS
  Eccentric endurance exercise economically improves glucose tolerance and LDL cholesterol. It therefore is a promising new exercise modality for individuals who are not able to participate in more strenuous exercise regimens.
authors.affiliation: Vorarlberg Institute for Vascular Investigation and Treatment, Feldkirch, Austria.
authors.forename: Markus
authors.initials: M
authors.lastname: Zeppetzauer
authors.forename: Heinz
authors.initials: H
authors.lastname: Drexel
authors.forename: Alexander
authors.initials: A
authors.lastname: Vonbank
authors.forename: Philipp
authors.initials: P
authors.lastname: Rein
authors.forename: Stefan
authors.initials: S
authors.lastname: Aczel
authors.forename: Christoph H
authors.initials: CH
authors.lastname: Saely
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001317:Austria; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism*; D018592:Cross-Over Studies; D004734:Energy Metabolism; D005080:Exercise Test; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D018836:Inflammation Mediators / Q000097:blood*; D008055:Lipids / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010807:Physical Endurance; D057185:Sedentary Behavior; D013997:Time Factors; D016896:Treatment Outcome; D016138:Walking
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D018836:Inflammation Mediators; D008055:Lipids