Q: What is the difference between Anaerobic Threshold (AT), Lactate Threshold (LT), Ventilatory Threshold (VT) and Maximal Steady State (MSS)?
A: Anaerobic Threshold (AT) was a term applied to the lactate inflection point, or the point at which the appearance of lactate in the blood accumulates faster that its rate of use. It was once thought (incorrectly) that a lack of sufficient oxygen to muscle shifted energy delivery to anaerobic metabolism, resulting in an increase in lactate production thus causing fatigue. Since lactate does not cause fatigue, nor does it determine anaerobic metabolism, the misnomer anaerobic threshold was rejected as a concept nearly two decades ago. Simply speaking, no “anaerobic” threshold exists.
Lactate Threshold (LT) is a more recent and descriptive term for the lactate inflection point described above. Due to the misconception about lactate as the source of fatigue, it was thought that the workload just below lactate accumulation in the blood reflected a maximum sustainable level of performance (typically measured as a 1 hr time trial). Despite the fact that LT is a more descriptive name for the lactate inflection point than AT, current research suggests that it tends to underestimate time trial performance. Perhaps more important to consider is that there are no fewer than four different established methods of measuring and interpreting LT. Since the exercise science field has not agreed upon a single method, and each method can produce a different set of results for a given athlete, LT has questionable reliability and accuracy in measuring performance.
Ventilatory Threshold (VT) describes the inflection point for ventilation during an incremental exercise test. Ventilation increases at about the same rate as oxygen consumption up to about 50-70% of VO2max (depending on one’s trained level). At this point (just beyond the ventilatory threshold) ventilation increases exponentially. Some researchers have identified two ventilatory thresholds. Although ventilation is not a limiter to performance, there is evidence suggesting that power at VT predicts average power for a 40km time trial. However, similar to LT tests, there are multiple VO2max test designs and the validity of the results vary by test. More important to measuring performance and training application using a heart rate monitor, VT may not accurately and reliability predict time trial (threshold) heart rate.
Maximal Steady State (MSS)
Regardless of lactate appearance or the rate of ventilation, as athletes we really just want to know how hard to train or how fast we can go in a race. We are interested in measuring and predicting real-world performance – a functional, performance threshold. More specifically, what is the maximum sustainable output (represented by workload and heart rate) for a given period of time (e.g. 30 min)? Maximal Steady State (MSS) is that performance threshold.
Q: Does Whole Athlete offer VO2max or lactate testing?
A: After carefully researching VO2max and lactate testing, we discovered that these methods do not provide power and HR data with the same accuracy and real-world application as our power-based MSS protocol. VO2 data are interesting and provide a snapshot of the general level of cardiovascular fitness one has. But VO2max does not predict performance and is less directly applicable to training and performance in cycling than MSS and subsequent power/heart rate zones. For example, an athlete can significantly increase max sustainable power without altering VO2max.
Q: What is the advantage to using Whole Athlete’s MSS test over other protocols?
A: Our unique testing protocol currently has the highest level of validity (accuracy) and reliability in determining both Maximal Steady State (MSS) power and heart rate. Although there are interesting data collected via lactate and VO2max testing, it is unnecessary to sample blood or wear a VO2 mask to most accurately predict and measure performance. MSS power and heart rate are all you need.
Q: How are my training zones determined from the test?
A: Heart rate and power training zones are percentages of MSS heart rate and corresponding power output. These levels of intensity are unique to each individual. Training zones are defined by workloads requiring specific muscle fiber type recruitment (Type I, IIa, IIb) and their metabolic demands (fuels and energizing pathways).
Q: Why don’t I just base my training on maximum heart rate?
A: When first applied to training, maximum heart rate (HRmax) was thought to be the benchmark for HR training values. However, this concept has been challenged since the 1970’s. HRmax is no longer used to determine a cyclist’s threshold or training zones because it can skew the accuracy of estimating training intensity by as much as 30%. Here’s the problem: HRmax is difficult to accurately determine because it decreases with age and varies with training, and it can vary significantly depending on you body temperature or even your level of fatigue. A more effective and reliable method to estimate training intensity is to measure your 30-minute performance threshold HR (Maximal Steady State) and use it as the standard.
Q: How should I prepare for a max steady state test?
A: To accurately determine one’s threshold, a recovered state is essential. To not be sufficiently recovered from training or racing will negatively influence performance on the test. In other words, be rested for the test in the same manner as you would for a race, i.e. no hard training/racing for at least 48hrs.
Q: How often should I perform a max steady state test?
A: Testing is a useful benchmark to either depart from on a new training program, or to compare with previous tests after significant training or racing periods. Since the test is typically shorter and less taxing than performing a time trial, it is a useful periodic measurement of fitness and performance. The test can be performed at various times throughout the year, as often as every 2-6 months.
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