Table 1

Exercise prescription adherence by group and substrate use

Low amount/moderate intensityLow amount/vigorous intensityHigh amount/vigorous intensity
n575864
Prescription and actual exercise dose
    Intensity (% peak oxygen consumption)40–55%65–80%65–80%
    Prescription amount (miles/week)*121220
    Prescription amount (kcal/week)1,220 ± 2121,230 ± 1772,020 ± 307
    Prescription time (min/week)201 ± 37125 ± 28207 ± 44
    Adherence (%)88 ± 1490 ± 1284 ± 15
    Actual amount (miles/week)10.610.816.8
    Actual time (min/week)176 ± 36113 ± 28172 ± 41
    Frequency (sessions/week)3.5 ± 0.82.9 ± 0.53.6 ± 0.8
    Respiratory exchange ratio0.907 ± 0.05§0.960 ± 0.060.961 ± 0.04
Fat utilization
    Energy from fat (%)30.2%12.6%12.6%
    kcals from fat (kcal)368155255
  • Data are means ±SD.

  • *Prescription amount is presented as the approximate number of miles/week that are calorically equivalent to the prescribed kcal/week of 14 kcal · kg body wt−1 · week−1 for the low-dose groups and 23 kcal · kg body wt−1 · week−1 for the high-dose group.

  • †Actual amount = prescription amount × adherence for each group (therefore no SD).

  • ‡Actual time = prescription time × adherence for each subject. Respiratory exchange ratios were obtained during the submaximal exercise bout that was performed to determine the correct exercise intensity (i.e., 40–55% for the moderate-intensity group and 65–80% for the vigorous-intensity groups).

  • §Respiratory exchange ratio for the moderate-intensity group was significantly different from both vigorous groups (P < 0.0005).