Is a verification phase needed to determine O_2max across fitness levels?

Area of Science:

• Exercise Physiology
• Cardiorespiratory Fitness Assessment
• Sports Science

Background:

• Current methods for determining maximal oxygen consumption (VO2max) using plateau or secondary criteria are often inconsistently achieved.
• This inconsistency leads to questions about the reliability of VO2max measurements and suggests the need for verification phases (VP).
• The efficacy of a VP in confirming VO2max across different fitness levels requires further investigation.

Purpose of the Study:

• To provide evidence supporting the use of a verification phase (VP) to confirm maximal oxygen consumption (VO2max).
• To assess the effectiveness of a VP in confirming VO2max across individuals with varying fitness levels.

Main Methods:

• Forty-nine participants underwent three graded exercise tests (GXT) with subsequent verification phases (VP) at 85%, 95%, and 105% of the final workload.
• Participants were categorized into fitness groups based on American College of Sports Medicine (ACSM) VO2max guidelines.
• VO2max was confirmed if the peak oxygen consumption (VO2peak) during the VP or an additional GXT was within ±2x the typical error of the initial GXT's VO2peak.

Main Results:

• The VO2peak from the initial GXT was not significantly different from the VO2peak obtained during VPs at 95% or 105% workload, or during a second GXT.
• A VP at 85% workload yielded a significantly lower VO2peak compared to the initial GXT.
• Verification phases at 105% workload or a second GXT confirmed the initial VO2peak in 73% of participants, with no significant differences observed across fitness levels.

Conclusions:

• A verification phase (VP) utilizing a 105% workload or performing a second graded exercise test (GXT) can reliably confirm maximal oxygen consumption (VO2max).
• This confirmation of VO2max is effective across a spectrum of fitness levels.
• Submaximal VPs (85% and 95%) were less effective in confirming VO2max, with a notable percentage of participants achieving higher VO2peak values on subsequent GXTs.