Anaerobic Energy/Work Supply in Endurance Activities – The Importance and Effect of Computational Method

Physiologically, performance in short-duration and longer duration endurance events is usually described by the total energy provision, i.e., the sum of aerobic and anaerobic energy supply, and the gross mechanical efficiency or the energy cost of movement. Due to the limited capacity of the anaerobic energy supply, the relative anaerobic contribution decreases with exercise duration. Nevertheless, also in endurance events over a relatively long duration, anaerobic energy provision is crucial for breakaways and final end-spurts as well as for optimizing pacing strategies over undulating terrain – likely making anaerobic capacity/anaerobic power more important to performance than initially thought. While aerobic energy provision during exercise can be quantified by using respiratory measures of oxygen consumption and carbon dioxide production, quantification of the anaerobic energy provision is more complicated, and several different methods have been used.

Currently, there is a clear mismatch between the total number of studies that have quantified anaerobic capacity during whole-body exercise by using one method and related it to performance vs. the amount of research that has aimed to enhance the methodological understanding by comparing results generated by different computational methods. Potential explanations for why the methodological research is limited could be the lack of a gold standard procedure for evaluating the accuracy of different methods of estimating anaerobic capacity and the substantial time investment that comes with multiple laboratory sessions. To date, there are several different methods available for estimating the anaerobic capacity, or anaerobic work capacity, during endurance activities such as running, cycling, rowing, roller-skiing, etc. Here, the most common approaches are the maximal accumulated oxygen deficit method (MAOD), the GE method, and the critical power (or critical speed) concept. We believe it is time for a more rigorous methodological evaluation of different methodological concepts for quantifying anaerobic capacity. This, because such information would facilitate the decision-making process when designing test-protocols as well as to enhance the overall quality of generated test results. In addition, research addressing the link between anaerobic energy provision, pacing strategies, and its impact on exercise performance is welcomed.

In this Research Topic, we ask for papers including at least one common measure of anaerobic energy supply (or anaerobic work) during exercise modalities lasting longer than approximately two minutes. We welcome original research, narrative reviews, systematic reviews with or without meta-analysis, commentaries, and perspectives. Preferably, on some of the topics that are listed below:
• The agreement between different methods of estimating anaerobic capacity
• The impact of different submaximal test protocols on the anaerobic capacity measures
• The test-to-test reliability of anaerobic capacity determined with different methods
• The link between pacing and endurance performance in relation to anaerobic energy provision
• The contribution from anaerobic and aerobic energy sources during highly intermittent endurance exercise, i.e., supramaximal exercise that is interspersed with submaximal exercise
• The effect of glycogen availability on anaerobic capacity
• The effect of supramaximal exercise on gross efficiency, or movement economy, and its impact on the choice of methodological concept for determining anaerobic capacity

All submitted papers should include a thorough methodological discussion.