E Daines | PubMed Health

PubMed1996

Predicting functional capacity during treadmill testing independent of exercise protocol.

Clinically useful estimates of VO2max from treadmill tests (GXT) may be made using protocol-specific equations. In many cases, GXT may proceed more effectively if the clinician is free to adjust speed and grade independent of a specific protocol. We sought to determine whether VO2max could be predicted from the estimated steady-state VO2 of the terminal exercise stage. Seventy clinically stable individuals performed GXT with direct measurement of VO2. Exercise was incremented each minute to optimize clinical examination. Measured VO2max was compared to the estimated steady-state VO2 of the terminal stage based on ACSM equations. Equations for walking or running were used based on the patient's observed method of ambulation. The measured VO2max was always less than the ACSM estimate, with a regular relationship between measured and estimated VO2max. No handrail support: VO2max = 0.869.ACSM -0.07; R2 = 0.955, SEE = 4.8 ml.min-1.kg-1 (N = 30). With handrail support: VO2max = 0.694.ACSM + 3.33; R2 = 0.833, SEE = 4.4 ml.min-1.kg-1 (N = 40). The equations were cross-validated with 20 patients. The correlation between predicted and observed values was r = 0.98 and 0.97 without and with handrail support, respectively. The mean absolute prediction error (3.1 and 4.1 ml.min-1.kg-1) were similar to protocol-specific equations. We conclude that VO2max can be predicted independent of treadmill protocol with approximately the same error as protocol-specific equations.

Adult↗

PubMed1996

Athletic performance in relation to training load.

Athletic performance generally is thought to improve with increases in training load. However, few data exist showing the quantitative relationship between training load and performance. We followed 56 athletes (16 runners; 40 cyclists/speed skaters) during 12 weeks of training. We recorded index performances (3.2 km time trial or 5 or 10 km bicycle ergometry) after 6 weeks of baseline training and 6 weeks of a self-selected training increases. Training load was quantitated as the product of intensity (global rating of perceived exertion (RPE)) and the duration (time) of each training session. Load was expressed as the weekly average over the 6 weeks preceding each index performance. We also recorded the duration of high intensity training (RPE>5, hard) (inten). From 6 to 12 weeks, performance improved 12.95 +/- 3.83 to 12.66 +/- 3.00 min (p < .01). Training time (345 +/- 282 to 355 +/- 273 min/wk) and inten (61 +/- 88 to 71 +/- 91 min/wk) did not change significantly, although RPE (3.8 +/- 0.7 to 4.0 +/- 0.8) and load (1242 +/- 957 to 1386 +/- 978) increased significantly. No strong correlations existed between changes in performance and changes in any training measure (TIME, r = -0.031, RPE, r = -0.039, LOAD, r = 0.29, INTEN, r = 0.025.) Data suggest that improved performance in events of 7-20 minutes duration in response to intensified training is primarily dependent upon increases in total load and overall RPE during training and; that a 10-fold increase in training load may be associated with an approximately 10% improvement in performance. These data suggest the possibility of understanding the training responses of athletes on a quantitative basis.

Adult↗