Peak Running Velocity or Critical Speed Under Field Conditions: Which Best Predicts 5-km Running Performance in Recreational Runners?

This study aimed to examine which variable, between the peak running velocity determined on the track field (V-peak_TF) and critical speed (CS), is the best predictor of the 5-km running performance in recreational runners. Twenty-five males performed three tests to determine the V-peak_TF, CS, and 5-km running performance on the track field, with a minimal interval of 48 h between each test. The V-peak_TF protocol started with a velocity of 8 kmh(-1), followed by an increase of 1 kmh(-1) every 3 min until volitional exhaustion, which was controlled by sound signals, with cones at every 25 m indicating when the participants were required to pass the cone's position to maintain the required velocity. The participants performed three time trials (TTs) (1: 2,600 m; 2: 1,800 m; and 3: 1,000 m) on the same day, with a 30-min rest period to determine the CS through the combinations of three (CS1,(2),(3)) and two TTs (CS1,(2), CS1,(3), and CS2,(3)). The 5-km running performance time was recorded to determine the test duration, and the mean velocity (MV) was calculated. There was a significant difference observed between the V-peak_TF and the MV 5-km running performance. However, no differences were found between the CS values and the MV 5-km running performance. A correlation was observed between the V-peak_TF (R = -0.90), CS1,(2),(3) (R = -0.95), CS1,(3) (R = -0.95), and the 5-km running performance time. Linear regression indicated that the V-peak_TF (R-2 = 0.82), CS1,(2),(3) (R-2 = 0.90), and CS1,(3) (R-2 = 0.90) significantly predicted the 5-km running performance time. The CS results showed a higher predictive power for the 5-km running performance, slightly better than the V-peak_TF. Also, CS1,(2),(3) and the CS1,(3) presented the highest predictive power for the 5-km running performance of recreational runners.