Author(s): YANG, W.H., PARK, S., GEHLERT, S., Institution: CHA UNIVERSITY, Country: KOREA, SOUTH, Abstract-ID: 169

INTRODUCTION:
The glycolytic system supports the metabolic energy requirements during intense exercise. The formula of maximal glycolytic rate (Mader’s model) is considered the delta lactate between maximal blood lactate accumulation after a 10-15 s exercise and resting blood lactate levels are divided by the difference between the total exercise time and phosphagen system-contributed time (tPCr). However, this formula does not subtract the energy contribution of oxidative metabolism. Furthermore, tPCr is assumed in which no lactate production takes place (“fictitiously”) although it is well known that lactate production occurs independently of oxygen availability under anoxic, hypoxic, and normoxic conditions. The point of −3.5% from the peak power output (tPCr −3.5%) was utilised in previous studies without providing an in-depth explanation on why the decreased 3.5% time point of the peak power output was used as tPCr. However, this method was based on an error in the early SRM cycle ergometer. Therefore, we modified the limitations of the previous formula and compared different calculations of the maximal glycolytic rate.
METHODS:
Calculations of the maximal glycolytic rate were based on the differences in defining the phosphagen-contributed time and incorporating the oxidative energy system contribution. In different calculations of the maximal glycolytic rate, tPCr −3.5%, tPCr−peak (the time until peak power output using the latest SRM cycle ergometer [± 0.5-1% error]), and incorporation of the oxidative energy system contribution for pure maximal glycolytic rate using the analysis of the PCr-La−-O2 method during a 15-s maximal cycling test were used.
RESULTS:
The level of maximal glycolytic rate (tPCr −3.5%) was higher than pure maximal glycolytic rate and maximal glycolytic rate (tPCr−peak) while maximal glycolytic rate (tPCr−peak) was lower than pure maximal glycolytic rate (p < 0.0001, respectively). A very high association between pure maximal glycolytic rate and maximal glycolytic rate (tPCr−peak) was observed (r = 0.99). This association was higher than the relationship between pure maximal glycolytic rate and maximal glycolytic rate (tPCr −3.5%) (r = 0.87).
CONCLUSION:
Pure maximal glycolytic rate as a novel calculation of maximal glycolytic rate provides more detailed insights into inter-individual differences in energy and glycolytic demands than other calculations of maximal glycolytic rate (tPCr−peak and tPCr −3.5%). In particular, because oxidative and phosphagen contributions can differ remarkably between elite track cyclists, implementing those values in pure maximal glycolytic rate can establish more optimized individual responses for elite track cyclists.