Lucia et al (2003) based their measure of TL around the ventilatory thresholds (VT1 & VT2). The method provides three zones: low (<VT1), moderate (VT1 - VT2) and high (>VT2). Each zone is given a coefficient of 1, 2 and 3, respectively. Time spent in each zone is multiplied by the relevant coefficient and summated to provide a TRIMP score. However, like Edwards (1993), the coefficients are not based on any scientific evidence and/or physiological data. Earlier work by Banister et al (1975) with swimmers used the same weighting coefficients (1 ,2, and 3) for low, moderate and high-intensity work, however he changed his approach to later base weighting on the blood lactate response. This sort of weighting implies that exercise at high-intensity is three times as demanding as exercise at low intensity. Lucia used this method to successfully compare the training load distribution in two different cycling tours. They reported no significant difference in the TL calculated by their method for two different cycling tours (Veulta a Espana compared to the Tour de France). Training using this three-zone model in endurance sports has received some attention (Esteve-Lanao et al., 2007, Seiler and Tonnessen, 2009), giving the method credence due it’s use in elite settings. Seiler described the polarized training methods popular with endurance athletes where ~80% of their training time is spent in zone 1 (<VT1). The metabolic thresholds used to identify the zones have shown to relate well to endurance performance (Amann et al., 2006). However the weightings remain arbitrary. This system appears to be best used by monitoring the time in each zone and the distribution in competion and training. This by no means dictates that a universal score from the associated coefficients is valid. Furthermore the weighting of each zone implies, that the training adaptation would be the same regardless of where in the zone an athlete trained. For example if the threshold for VT2 is identified at 85% of HRmax a training session with an intensity of 95% of HRmax would be given the same weighting as a training session at 85% of HRmax but different to if the athlete trained at 84%. The study of Denadai et al (2006) shows how a 5% difference in training intensity (95%vVO2max vs 100%vVO2max) produced different training adaptations. However, Impellezerri et al (2005) did demonstrate that training below and above such thresholds may produce differing training responses in soccer players (although the threshold was based on an arbitrary lactate value). But monitoring just high intensity activity in isolation means that the accrued training load from below the high intensity threshold could end up being ignored. To date no training study on Lucia’s method has been conducted to validate it by demonstrating dose-response relationships.
Do you use zones? What do you think? Useful? Let us know your thoughts in the training zones forum.
AMANN, M., SUBUDHI, A. W. & FOSTER, C. 2006. Predictive validity of ventilatory and lactate thresholds for cycling time trial performance. Scand J Med Sci Sports, 16, 27-34.
BANGSBO, J. 1994. The physiology of soccer--with special reference to intense intermittent exercise. Acta Physiol Scand Suppl, 619, 1-155.
BANISTER, E. W. 1991. Modeling Elite Athletic Performance. In: MACDOUGALL, J. D., WENGER, H. A. & GREEN, H. J. (eds.) Physiological Testing of Elite Athletes. Champaign, Illinois: Human Kinetics.
BANISTER, E. W., CALVERT, T. W., SAVAGE, M. V. & BACH, A. 1975. A system model of training for athletic performance. Aust J Sports Med, 7, 170-176.
DENADAI, B. S., ORTIZ, M. J., GRECO, C. C. & DE MELLO, M. T. 2006. Interval training at 95% and 100% of the velocity at VO2 max: effects on aerobic physiological indexes and running performance. Appl Physiol Nutr Metab, 31, 737-43.
EDWARDS, S. 1993. The heart rate monitor book, New York, Polar Electro Oy.
ESTEVE-LANAO, J., FOSTER, C., SEILER, S. & LUCIA, A. 2007. Impact of training intensity distribution on performance in endurance athletes. J Strength Cond Res, 21, 943-9.
LUCIA, A., HOYOS, J., SANTALLA, A., EARNEST, C. & CHICHARRO, J. L. 2003. Tour de France versus Vuelta a Espana: Which is harder? Med Sci Sports Exerc, 35, 872-878.
SEILER, S. & TONNESSEN, E. 2009. Intervals, thresholds and long slow distance: the role of intensity and duration in endurance training. Sports Science, 13, 32-53.