Annual ECSS-Congress, Bruges 2012
Date & time:
||05.07.2017 / -
|Title of the paper:
Evaluation of Different Blood Lactate Threshold Concepts for Constant Load Performance Prediction in Handcycling
||Stangier, C.1, Abel, T.1,3, Zeller, S.1, Quittmann, O.J.1, Perret, C.2,3, Strüder, H.K.1
||German Sports University
||Institute of Movement and Neurosciences
1Institute of Movement and Neurosciences, German Sport University Cologne, Germany.
2Institute of Sports Medicine, Swiss Paraplegic Centre, Nottwil, Switzerland
3European Research Group in Disability Sport (ERGiDS)
Endurance capacity is one of the main performance determinants in handcycling, a steadily growing Paralympic discipline.1 The maximal lactate steady state (MLSS) provides crucial information about both training and fitness level of an athlete.2 Different exercise tests are currently in use to determine lactate thresholds (LT) to predict MLSS. This study aims to evaluate the precision of the two primarily applied concepts in handcycling.
In a repeated measures cross over design, 11 male highly trained spinal cord injured (Th12 to L1) handcyclists (age; 40±9 yrs, height; 183±8 cm, body mass; 74±8 kg) performed a graded exercise test (GXT) and a lactate minimum test (LMT) to determine a LT (LT4mmol·L-1 and LTLMT, respectively). Constant load tests (CLT; 30 min) at a workload corresponding to the LT were completed on a separate day to validate the criteria for MLSS (change of ≤1mmol·L-1 during the last 20 min). Oxygen uptake (VO2), heart rate (HR) and blood lactate (La) were measured during the exhaustive tests to determine peak values and recorded every 5 min during the CLT.
A paired t-test revealed no significant difference between the workloads at the determined thresholds (LT4mmol·L-1: 144±31 W vs. LTLMT: 134±15 W; p=0.119). While two-way ANOVAs with repeated measures showed no significant differences for VO2 (p≥0.07), fractional VO2 (p≥0.12) and LA (p≥0.07), HR was significantly higher (p≤0.04) during CLT at LT4mmol·L-1 compared to CLT at LTLMT. Determinations of LT4mmol·L-1 and LTLMT did not meet the criteria for MLSS within the CLT for 4 and 2 athletes, respectively.
As endurance training induced structural and metabolic adaptations have an effect on blood-lactate kinetics during exercise, the accuracy of LTLMT could be impaired.3 Similar but inverse results are verified for the fixed 4 mmol·L-1 lactate threshold overestimating the MLSS in highly trained endurance athletes.2 While both exercise tests revealed valid estimates to predict a constant load performance for handcyclists, responses of elite athletes should be analysed individually and verified by means of several CLT. Considering this limitation, the current data enable coaches in handcycling to choose an adequate exercise test to assess performance data and derive exercise regimen.
1Abel T., Burkett B., Schneider S., Lindschulten R., Strueder HK. (2010). Spinal Cord, 48(12), 894-8.
2Faude O., Kindermann W., Meyer T. (2009). Sports Med, 39(6), 469-90.
3Hood DA. & Saleem A. (2007). Nutr Metab Cardiovasc Dis, 17(5), 332-7.
||Adapted Physical Activity