Blood Lactate Concentrations are Mildly Affected by Mobile Gas Exchange Measurements

Abstract

We sought to investigate the effects of wearing a mobile respiratory gas analysis system during a treadmill test on blood lactate (bLa) concentrations and commonly applied bLa thresholds. A total of 16 recreational athletes (31±3 years, V̇O_2max: 58±6 ml · min⁻¹ · kg⁻¹) performed one multistage treadmill test with and one without gas exchange measurements (GEM and noGEM). The whole bLa curve, the lactate threshold (LT), the individual anaerobic thresholds according to Stegmann (IAT_St) and Dickhuth (IAT_Di), and a fixed bLa concentration of 4 mmol ∙ l⁻¹ (OBLA) were evaluated. The bLa curve was shifted slightly leftward in GEM compared to noGEM (P<0.05), whereas the heart rate response was not different between conditions (P=0.89). There was no difference between GEM and noGEM for LT (2.61±0.34 vs. 2.64±0.39 m · s⁻¹, P=0.49) and IAT_St (3.47±0.42 vs. 3.55±0.47 m · s⁻¹, P=0.12). However, IAT_Di (3.57±0.39 vs. 3.66±0.44 m · s⁻¹, P<0.01) and OBLA (3.85±0.46 vs. 3.96±0.47 m · s⁻¹, P<0.01) occurred at slower running velocities in GEM. The bLa response to treadmill tests is mildly affected by wearing a mobile gas analysis system. This also applies to bLa thresholds located at higher exercise intensities. While the magnitude of the effects is of little importance for recreational athletes, it might be relevant for elite athletes and scientific studies.

Key words

cardiopulmonary exercise testing - performance diagnostics - lactate threshold - V̇O_2max - metabolic device

• References

• 1 Aaron EA, Seow KC, Johnson BD, Dempsey JA. Oxygen cost of exercise hyperpnea: implications for performance. J Appl Physiol 1992; 72: 1818-1825
• 2 Acevedo EO, Goldfarb AH. Increased training intensity effects on plasma lactate, ventilatory threshold, and endurance. Med Sci Sports Exerc 1989; 21: 563-568
• 3 Bosquet L, Leger L, Legros P. Methods to determine aerobic endurance. Sports Med 2002; 32: 675-700
• 4 Coen B, Urhausen A, Kindermann W. Individual anaerobic threshold: methodological aspects of its assessment in running. Int J Sports Med 2001; 22: 8-16
• 5 Dickhuth HH, Yin L, Niess A, Röcker K, Mayer F, Heitkamp HC, Horstmann T. Ventilatory, lactate-derived and catecholamine thresholds during incremental treadmill running: relationship and reproducibility. Int J Sports Med 1999; 20: 122-127
• 6 Epstein Y, Stroschein LA, Pandolf KB. Predicting metabolic cost of running with and without backpack loads. Eur J Appl Physiol 1987; 56: 495-500
• 7 Faude O, Kindermann W, Meyer T. Lactate threshold concepts: how valid are they?. Sports Med 2009; 39: 469-490
• 8 Harriss DJ, Atkinson G. Update – ethical standards in sport and exercise science research. Int J Sports Med 2011; 32: 819-821
• 9 Jeacocke NA, Burke LM. Methods to standardize dietary intake before performance testing. Int J Sport Nutr Exerc Metab 2010; 20: 87-103
• 10 Kindermann W, Simon G, Keul J. The significance of the aerobic-anaerobic transition for the determination of work load intensities during endurance training. Eur J Appl Physiol 1979; 42: 25-34
• 11 Knapik J, Harman E, Reynolds K. Load carriage using packs: a review of physiological, biomechanical and medical aspects. Appl Ergon 1996; 27: 207-216
• 12 Mader A, Liesen H, Heck H, Philippi H, Rost R, Schürch P, Hollmann W. Zur Beurteilung der sportartspezifischen Ausdauerleistungsfähigkeit im Labor. Sportarzt Sportmed 1976; 27: 80-88 109-112
• 13 Midgley AW, Bentley DJ, Luttikholt H, McNaughton LR, Millet GP. Challenging a dogma of exercise physiology: does an incremental exercise test for valid VO2max determination really need to last between 8 and 12 minutes?. Sports Med 2008; 38: 441-447
• 14 Mujika I, Padilla S. Cardiorespiratory and metabolic characteristics of detraining in humans. Med Sci Sports Exerc 2001; 33: 413-421
• 15 O’Donnell DE, Hong HH, Webb KA. Respiratory sensation during chest wall restriction and dead space loading in exercising men. J Appl Physiol 2000; 88: 1859-1869
• 16 Pfitzinger P, Freedson PS. The reliability of lactate measurements during exercise. Int J Sports Med 1998; 19: 349-357
• 17 Siler WL. Is running style and economy affected by wearing respiratory apparatus?. Med Sci Sports Exerc 1993; 25: 260-264
• 18 Sjodin B, Jacobs I. Onset of blood lactate accumulation and marathon running performance. Int J Sports Med 1981; 2: 23-26
• 19 Stegmann H, Kindermann W, Schnabel A. Lactate kinetics and individual anaerobic threshold. Int J Sports Med 1981; 2: 160-165
• 20 Stemler FW, Craig FN. Effects of respiratory equipment on endurance in hard work. J Appl Physiol 1977; 42: 28-32
• 21 Wood HE, Mitchell GS, Babb TG. Breathing mechanics during exercise with added dead space reflect mechanisms of ventilatory control. Respir Physiol Neurobiol 2009; 168: 210-217
• 22 Wood HE, Mitchell GS, Babb TG. Short-term modulation of the exercise ventilatory response in young men. J Appl Physiol 2008; 104: 244-252