A Preliminary Study on the Effect of Loaded and Unloaded Exercise on Anabolic and Turnover Activity of Articular Cartilage in Healthy Young Adults

The serum concentration of cartilage oligomeric matrix protein (sCOMP) has been considered a mechano-sensitive biomarker of articular cartilage turnover, and N-propeptide of type II collagen (PIIANP) is a proposed biomarker of type II collagen synthesis. Few studies have investigated both the anabolic and turnover response of articular cartilage as a result of acute changes in body weight mass during exercise. Using a repeated measures cross-over design, fifteen healthy adults (age 18-30 years) performed three, 30-minute bouts of treadmill walking exercise under 3 loading conditions: (1) control (no alteration to body mass); (2) loaded (12% increase in body mass using a weighted vest); and (3) unloaded (12% decrease in body mass using lower body positive pressure). Venous blood was collected before, immediately after, and 15 and 30 minutes after exercise to investigate cartilage turnover (sCOMP) and anabolism (PIIANP).