Related Experiment Video
Updated: Aug 12, 2026

Determining the Contribution of the Energy Systems During Exercise
Published on: March 20, 2012
Aerobic and anaerobic power characteristics of off-road cyclists
1Institute of Sports Science, Department of Prevention and Rehabilitation and Sports Medicine, University of Vienna, Austria. ramon.baron@univie.ac.at
Purpose:
The purpose of this study was to describe the relationship between anaerobic power at different pedaling frequencies (including the optimal cadence) and aerobic power in off-road cyclists (CYC; N = 25) and sports students, who did not perform specific cycle exercise more than two times per week (CON; N = 60).
Methods:
To describe the aerobic power, we measured the maximal power output (W(max)) and the power output at the fixed lactate threshold at 4 mmol x L(-1) (W(L4)) obtained during a maximal aerobic power cycling test. To describe anaerobic power output, we measured the average power output (IsoW(mean)) over a range from 50 to 140 rpm by using a 10-s sprint on an isokinetic cycle ergometer.
Results:
For the 10-s anaerobic test, CON and CYC showed a peak power output (IsoW(peak)) of 13.3 +/- 1.4 and 14.9 +/- 1.1 W x kg(-1), respectively. IsoW(peak) corresponded to an optimal cadence of 100 +/- 9.3 rpm for CON and 100 +/- 8.7 rpm for CYC. There was a significant difference (P < 0.001) in the W(max):IsoW(peak) (W(aerobic):W(anaerobic)) ratio between CON (32 +/- 4.5%) and CYC (38 +/- 3.9%). Significant differences among group means were identified using an ANOVA test and a post hoc analysis. The off-road cyclists showed a significantly higher IsoW(mean) at all pedaling frequencies and at the optimal cadence (P < 0.01). There was a modest relationship between W(max) and IsoW(peak) in both groups (CON r = 0.53; CYC r = 0.64; P < 0.01).
Conclusion:
Anaerobic power values are important components associated with cycle performance in both noncyclists and off-road cyclists. However, the results of the present study demonstrated the usefulness of the power index in the physiological evaluation of off-road cyclists, as it gives information on the proportion of aerobic to anaerobic energy contribution.
More Related Videos
Related Concept Videos
Classification of Skeletal Muscle Fibers
Slow-Twitch Muscle Fibers
Slow oxidative, muscle fibers appear red due to large numbers of capillaries and high levels of...
Energy Supply for Muscle Contraction
Muscle Recovery and Fatigue
Types of Skeletal Muscle Fibers
Fast-twitch fibers
Fast-twitch fibers, or Type II fibers, are designed for quick, powerful bursts of speed and strength. They reach peak tension within approximately 0.01 seconds following stimulation. Characterized by a large diameter and densely packed myofibrils, these fibers contain...
Exercise and Muscle Performance
Endurance exercises
Endurance exercises involve running, swimming, or cycling, which require repetitive movements with low force output. When a person engages in endurance exercise, a few noticeable changes occur in their skeletal muscles. For instance, the number of capillaries...
Oxygen Requirements and Growth Patterns

