Segment-Specific Relationship Between Anaerobic Critical Velocity and 100-m Front Crawl Performance in a 25-m Pool

Anaerobic critical velocity (AnCV) has been proposed as a practical index for evaluating anaerobic swimming performance, but the race segments or phases of a 100-m swim that it best represents is not clear. This study aimed to examine the relationships between AnCV and mean swimming velocities (MSVs) across different segments and phases of a 100-m maximal front crawl.

Eighteen collegiate male swimmers performed 10-, 15-, 20-, and 25-m maximal front crawl swims to calculate AnCV. MSVs were derived from split times recorded at 15, 25, 40, 50, 65, 75, 90, and 100 m. Both segmental MSVs (eg, MSV0-25m) and phase-specific MSVs (start, stroke, and turn-out) were analyzed.

AnCV demonstrated strong positive correlations (Spearman ρ) with MSV0-25m, MSV25-50m (ρ = .51-.55, P ≤.03), and stroke phases at 15 to 25 m and 65 to 75 m (ρ = .55-.57, P ≤.02). Moderate correlations were observed with MSV0-100m, start phase, and stroke phase at 40 to 50 m (ρ = .47-.55, P ≤.04).

These findings indicate that AnCV primarily reflects performance in the early segments of a 100-m swim, particularly during stroking phases, and thus represents a practical tool for monitoring performance and guiding training strategies in competitive swimmers.