I like to give here a reply on a very common question we are getting over the last few month.
This may help many readers to have some better ideas on what we work towards.
Roger here some feedback to your interesting email
“Hello, I am a strength coach working with flat-water kayakers. How can I assess, program, and monitor athletes using Moxy? Does it help me figure out lactate threshold? Do I program training's around heart rate or cadence that correspond with oxygenation at certain levels during an assessment? Cheers XYZi”
1. Water sports like rowing , kayaking but as well swimming may benefit much more by using NIRS/MOXY , than many coaches for the moment do not recognize.
Why? This are all sports (certainly rowing and Kayaking) where at the start you have to go hard to get the boats into surf position to reduce water drag to a minimum. On the other side you have options (stroke rate versus stroke length and more, pretty much like in cycling with RPM and so on. MOXY will help to see, what is better at the moment and how I can change into what I may like to have. In a 4 men rowing boat we may have one member who will have a utilization problems in a 40 stroke rate due to an occlusion build up where another member may have a utilization problem due to lower mitochondria density and vascularisation. So both need a very different training intervention. In the past only an experience coach may have picked that up ( IF ).
So here some short starter answers to the questions.
1. How can I assess
In a race situation first and foremost. You like to see, what limits the race performance and then can plan from there.
Once you have the limitation from the race performance (utilization /’ delivery) you make the three options we use for testing. TRIP as a Trip though TIP (training intensity profile) to find intensities for improvement of vasuclarisation. Mitochondria density, cardiac limitation or respiratory limitations or technical coordination intensities.
Than you make a RIP Recovery intensity profile to find out duration of intervals, recovery times between loads and numbers of reps in a full workout. This as well is on the water and or on a kayaking erg.
Last but not least you make a SIP ( strength intensity profile to design the load and the duration as well as the reps for what you like to achieve with the sport specific strength.
2. program, and monitor athletes
The program is what you are always doing , so the change is only , that for the assessments as you now know the limitation and the compensation and you can now specifically use your training ideas to address this situation. Then you go and retest and see, whether the goal you had set is reached with what you planned in your workouts.
The monitoring part is easy. In the gym big screen and live feedback during workouts.
On the water. The athletes over a Garmin watch FR 70 and the coach over a wasp systems from the boat who follows or in a rowing pool with roads on the side from a car over the PC and walkie talkie connection to the boat to correct and see live as you train.
3. Does it help me figure out lactate threshold?
Dangerous question for us to answer.
Some believe they can use NIRS to look for a lactate threshold or anaerobic threshold.
We have some open doubts about that because what theory is your idea of lactate threshold or anaerobic threshold.
. What muscles in the sport like this will contribute how much to what kind of a lactate concentration and even if you have lactate in the system is that really that bad and what does it means other , that somewhere in the body you creates a certain amount of a metabolic reaction, where lactate was as well involved to either buffer H + or was shuttled to be used on an other place or was simply too much in one area so got moved out over MCT1 and moved in over MCT4 in another area.
We do not use lactate as any kind of a tool for any intensity control nor any other info than looking from a nutritional point of view pre race or pre training whether the glycogen storage may be refueled or not. “ANAEROBIC THRESHOLD - A RELATIVELY USELESS CONCEPT FOR COACHING
Billat, L. V. (1996). Use of blood lactate measurements for prediction of exercise performance and for control of training: Recommendations for long-distance running. Sports Medicine, 22, 157-175.
This article contains a very concise summary of the concept of anaerobic threshold and how it is depicted in the literature. The implications of each individual statement are particularly important given the pre-occupation of many coaches with this concept. The major points of the article are discussed below. Further features are introduced in the "Implications" section.
The concept of anaerobic threshold itself is not universally consistent. Long dynamic exercise that is predominantly aerobic ranges between two extremes of physiological dynamics resulting in very different blood lactate levels.
- At the lowest level, an exercise can be sustained for a very long time. After 2-5 min a state of overall oxidative energy supply is established where lactate production is balanced by lactate elimination at a low level. Fat (lipid) metabolism is the primary source of fuel. Exercise limits are mainly associated with eventual increases in internal temperature. Potential dehydration can be prevented by supplementation of water and substrate (carbohydrate and electrolytes) during performance. (p. 158)
- At the highest extreme, the workload requires an additional formation and accumulation of lactate to maintain power output. Exhaustion results through the disturbance of the internal biochemical environment of the working muscles and whole body caused by a high or maximal acidosis. Generally, accumulation of H + limits performance to periods from 30 sec to 15 min. For example, the average time to exhaustion at the minimal velocity which elicits VO2max is 6:30 and is not correlated with the blood lactate level developed during the task. (p. 159)
Between these two extremes are transition stages, several of which are labelled similarly as "anaerobic threshold" or "lactate threshold." Thus, the same label is used for different concepts and their assessment protocols that lead to different values and training implications. Billat displays the various implications of this confusing situation. According to a variety of "authorities," changes in blood lactate accumulation are termed and defined differently as well as being associated with different levels and characteristics of accumulated lactate. H+ They are also differentiated by the protocols used to measure them. Some examples are listed below.
4. Do I program training around heart rate or cadence that. We would program around MOXY info as this is real live feedback so tHb and SmO2 trend information. RPE and HR as well as lactate are not optimal ways to find proper intensities for sport.
Eur J Appl Physiol. 2002 Jun;87(2):159-66. Epub 2002 Apr 18.
Reproducibility of the blood lactate threshold, 4 mmol.l(-1) marker, heart rate and ratings of perceived exertion during incremental treadmill exercise in humans.
Grant S1, McMillan K, Newell J, Wood L, Keatley S, Simpson D, Leslie K, Fairlie-Clark S.
- 1Institute of Biomedical and Life Sciences, University of Glasgow, 64 Oakfield Avenue, G12 8LT, UK. S. Grant@biomed.gla.ac.uk
The aim of this study was to investigate the reproducibility of blood lactate measurements, heart rate (HR) and ratings of perceived exertion (RPE) during treadmill exercise at speeds corresponding to the lactate threshold ( v(Th,la)-) and a fixed blood lactate concentration of 4 mmol.l(-1)( v(la)-(,4)). Possible differences in reproducibility related to fitness levels were also investigated. A group of 20 men [mean (SD)] [age 20.5 (1.4) years] and 16 women [age 21.2 (0.9) years] took part in the study. The subjects performed two identical incremental exercise tests consisting of at least six 4 min stages. Blood lactate concentrations, HR and RPE were recorded at the end of each stage. Limits of agreement (LoA), correlation coefficients and 95% confidence intervals for the mean difference between tests were employed to investigate the level of agreement and reproducibility of blood lactate concentration, HR and RPE. For the group as a whole, the sample correlation coefficient for speed at v(Th,la)- was r=0.88, and was r=0.92 for the speed at v(la)-(,4). At v(Th,la) -, the correlation coefficients for the moderately fit and unfit were r=0.94 and r=0.36, respectively, and at v(la)-(,4) r=0.93 and r=0.68, respectively. The LoA for the moderately fit group indicated that a change of 1.62 km.h(-1) in v(Th,la)- would be necessary to be considered a change in training status. For HR and RPE, relationships between the tests were generally poor. The LoA suggested that changes in scores must be unacceptably large. These findings cast doubt on the sensitivity of testing for change of blood lactate concentration, HR and RPE in this population.
Reproducibility of aerobic and anaerobic thresholds in 20-50 year old men.
Aunola S, Rusko H.
The reproducibility of the aerobic (AerT) and the anaerobic (AnT) threshold was studied in 33 men aged 20-50 years. They completed two maximal exercise tests on a bicycle ergometer. The thresholds, as VO2 (1 X min-1), were determined visually by two investigators using both the blood lactate and the respiratory indices. The respiratory variables were measured with a computerized breath-by-breath method; samples of venous blood were drawn every 2nd min and analysed enzymatically for lactate. The reproducibility of the AerT (r = 0.94) and of the AnT (r = 0.96) were equally good. The AnT can be determined either from blood lactate concentrations (AnTLa) or from ventilatory and gas exchange response (AnTr) during a 2-min incremental exercise test. They both also showed similar reproducibility: r = 0.93 for the AnTLa and r = 0.95 for the AnTr. The work rate and the measured physiological variables at the AerT and AnT, except for the blood lactacte concentration, were very reproducible. Age did not affect the reproducibility of the thresholds. The poor reproducibility of blood lactate concentration of the AnT confirmed our previous opinion that the fixed blood lactate levels of 2 and 4 mmol X 1(-1) are poor indicators of AerT and AnT.
And here another study which is really a summary for many studies done in teh late 1980 in Germany .
© 2013 Published by Elsevier Ltd on behalf of Sports Medicine Australia Reproducibility of lactate markers during 4 and 8 min stage incremental running: A pilot study James P. Gavin∗, Mark E.T. Willems, Stephen D. Myers Department of Sport and Exercise Sciences, University of Chichester, UK
This study examined the reproducibility of speed corresponding to specific lactate markers during incremental treadmill running of normal and prolonged stage durations. Design: Nineteen healthy participants (14 male, 5 female) performed repeated, incremental treadmill running trials of 4 and 8 min stages on separate days to examine the test–retest reproducibility of speed at lactate markers. Two trials were completed for each duration in a randomised order. Methods: Fingertip blood samples drawn upon stage completion were analysed for plasma lactate, the used to determine running speed at: 2.0, 3.5, and 4.0 mmol l−1fixed blood lactate accumulations (FBLA),a 1 mmol l−1rise from baseline, and the markers: the deviation maximum (Dmax), the Dmaxof the second curve derivative (D2Lmax), the lactate threshold (LT) and log–log LT.Results: The 2.0 mmol l−1FBLA reported the lowest mean bias between 4 min trials (−0.06 km h−1), with the narrowest limits of agreement (LoA) (−1.78 to 1.66 km h−1). The Dmaxhad the second lowest bias(0.14 km h−1), D2Lmaxthe second narrowest LoA (−1.93 to 2.90 km h−1). For 8 min stages, the 1 mmol l−1rise demonstrated, low mean bias (−0.13 km h−1) and narrowest LoA (−1.22 to 0.97 km h−1) between trials
This preliminary report suggests the reproducibility of running speed at lactate summary markers is influenced by stage duration for incremental treadmill running. Varied marker reproducibility between 4 and 8 min stages indicates different blood lactate response, and therefore workload calculation, according to stage length. Consideration of marker construct is recommended.
Hope this helps a little bit.