Comparison of alternative νLamax determination approaches in cycling and rowing

The maximal lactate accumulation rate (νLamax) offers an understanding of the athlete's maximum glycolytic power. The traditional νLamax determination requires multiple post-exercise lactate measurements, which are time-consuming and resource-intensive. Therefore, this study aimed to compare two simplified methods: a polynomial modelling approach (νLamax_Poly) and a single post-exercise lactate measurement at 5 minutes (νLamax_5min). Additionally, differences in νLamax between rowing and cycling, as well as sex-based variations, were examined. A total of 152 trained athletes performed maximal sprints on a rowing ergometer (20s) or a cycle ergometer (15s). Blood lactate was sampled at rest and every minute for 10 minutes post-exercise. Both alternative methods showed excellent agreement with the traditional approach (r = 0.99). While no bias was observed for νLamax_Poly, the νLamax_5min method exhibited a slight systematic underestimation (p < 0.001; MD: -0.019 ± 0.021 mmol/l/s). However, its narrower limits of agreement indicate slightly higher precision compared to νLamax_Poly. Rowers showed lower νLamax and peak lactate values than cyclists. Male participants exhibited higher νLamax, sprint power, and peak lactate than females. Overall, the findings suggest that νLamax_Poly and νLamax_5min provide valid and practical alternatives to traditional methods, facilitating wider application in research and field settings.