Preprint / Version 2

Validity of a simulation-based performance testing model in cycling

a study protocol


  • Jasper Suttmeyer Ruhr University Bochum, Department of Sports Medicine and Sports Nutrition
  • Anna Dmitrieva Ruhr University Bochum, Department of Sports Medicine and Sports Nutrition
  • Yves Reuter Ruhr University Bochum, Department of Sports Medicine and Sports Nutrition
  • Jan Venzke Ruhr University Bochum, Department of Sports Medicine and Sports Nutrition
  • Petra Platen Ruhr University Bochum, Department of Sports Medicine and Sports Nutrition
  • Robin Schäfer Ruhr University Bochum | Department of Sports Medicine and Sports Nutrition



maximal oxygen uptake, maximal lactate prodcution rate, anaerobic threshold, Endurance Performance, endurance diagnostics


Background: Metabolic simulations as described by Mader (2003) can be used to model the physiological response (e.g. blood lactate, phosphocreatine, pH, aerobic and anaerobic energy contribution) to exercise. While some parameters of the model were derived from the literature and are assumed to be constant, the individual performance markers V̇O2max (maximal oxygen consumption) and ċLamax (maximal lactate production rate) can be used as input to create individual performance predictions. Further, the MLSS (maximal lactate steady-state) can be estimated via the model. In practice, this model is already used to infer those performance markers from observed testing data. However, a thorough evaluation of this approach is still missing.

Objective: To assess the concurrent validity of simulation-based performance testing (sim) in cycling compared to experimental estimates from performance testing (exp).

Study Design: Agreement Study

Participants: Recreational cyclists and triathletes

Methods: Five exercise tests will be conducted on at least 5 days. On day 1, body composition, a 15-second sprint (ċLamaxexp) and a ramp test until exhaustion (V̇O2maxexp) will be conducted. On day 2 and 3, an individualized test protocol and a standard graded exercise test are conducted to observe model-based performance markers (V̇O2maxsim, ċLamaxsim, MLSSsim) with each procedure. From day 4 on, multiple 30-minute constant workload tests are performed to measure MLSSexp. Agreement analyses will be conducted via Bland-Altman analyses using a priori defined Limits of Agreement.

Registration: This study protocol will be pregistered via the Open Science Framework (OSF) upon an ethical vote.

Ethics: A vote by the ethics committee of the Ruhr University Bochum is still pending.


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2023-03-09 — Updated on 2023-03-09