Table 3 Absolute (units of measure per year) and relative (percentage per decade) cross-sectional rates of change in plasma concentration of purine metabolites and erythrocyte HGPRT activity in speed-power-trained, endurance-trained and untrained subjects.

From: Purine metabolism in sprint- vs endurance-trained athletes aged 20‒90 years

  Speed-Power Endurance Untrained Differences between slopes*
Absolute Relative Absolute Relative Absolute Relative P-level Effect size (η2)
Hxrest (µmol·l−1) 0.030†,‡ 17.6 0.026†,# 17.0 0.058‡,# 36.7 <0.001 0.33
Hxpost (µmol·l−1) 0.347†,‡ 43.1 0.291†,# 21.4 0.342‡,# 24.0 0.026 0.04
Hxpost-rest (µmol·l−1) 0.317 44.0 0.265 24.3 0.284 19.2 0.055 0.03
Xrest (µmol·l−1) 0.035 35.0 0.036 39.1 0.044‡,# 37.3 0.009 0.05
Xpost (µmol·l−1) 0.039 29.1 0.039 23.6 0.045 25.0 0.301 0.01
Xpost-rest (µmol·l−1) 0.004 4.1 0.002 1.8 0.006 7.1 0.617 <0.01
UArest (µmol·l−1) 0.796 2.8 0.720 2.4 0.199 0.6 0.087 0.02
UApost (µmol·l−1) 1.573†,‡ 4.9 1.049†,# 2.9 0.466‡,# 1.2 0.002 0.06
UApost-rest (µmol·l−1) 0.777†,‡ 18.2 0.329†,# 4.5 0.266‡,# 3.0 0.002 0.06
HGPRT (nmolIMP ·mgHB−1·h−1) 0.037†,‡ 0.5 0.072†,# 1.0 0.024‡,# 0.3 0.025 0.04
  1. *Significance of differences between the slopes of the regression lines.
  2. Statistical significance between absolute rates of change: post-hoc Scheffè test at P < 0.05: significantly different from untrained subjects. significantly different from endurance-trained athletes. #Significantly different from speed-power-trained athletes. Legend: Hx ‒ hypoxanthine, HGPRT ‒ hypoxanthine-guanine phosphoribosyltransferase, UA ‒ uric acid, X ‒ xanthine, rest ‒ resting value, post ‒ post-exercise value, post-rest ‒ difference between post-exercise and resting value.