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Updated: Jun 16, 2026

A Real-World High-Intensity Interval Training Protocol for Cardiorespiratory Fitness Improvement
Published on: February 22, 2022
The effect of training volume and intensity on competitive cyclists' efficiency
James Hopker1, Damian Coleman, Louis Passfield
1Centre for Sports Studies, University of Kent, Chatham Maritime, Chatham, Kent, ME4 4AG, UK. j.g.hopker@kent.ac.uk
Abstract:
The impact of different intensity training on cycling efficiency in competitive cyclists is unknown. Twenty-nine endurance-trained competitive male cyclists completed 3 laboratory visits during a 12-week training period. At each visit, their cycling efficiency and maximal oxygen uptake were determined. After the first visit, cyclists were randomly split into 2 groups (A and B). Over the first 6 weeks, between tests 1 and 2, group A was prescribed specific high-intensity training sessions, whereas group B was restricted in the amount of intensive work undertaken. After test 2 and for the second 6-week period, group B was allowed to conduct high-intensity training. Gross efficiency (GE) increased in group A (+1.6 +/- 1.4%; p < 0.05) following the high-intensity training, whereas no significant change was seen in group B (+0.1 +/- 0.7%; p > 0.05). Group B cyclists increased their GE between tests 2 and 3 (+1.4 +/- 0.8%; p < 0.05) but no changes in GE were observed in group A over this period (+0.4 +/- 0.4%; p > 0.05). Delta efficiency (DE) did not change significantly in either group across the study period. This study demonstrates that GE is increased following high-intensity training in competitive male cyclists after 12 weeks.
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