Category: High Intensity training

Analytics, Data, Data Analytics, High Intensity training, Sports Science

What’s New in the Lactate Threshold App: Anaerobic Speed Reserve, Flexible Training Zones, Maximum Speed and More

The Lactate Threshold app started as a simple tool to turn a step test into a clean set of threshold values. Over the past few development cycles it has grown into something closer to a complete profiling and prescription workspace. This post walks through the most significant additions — anaerobic speed reserve, maximum speed determination, switchable 3- and 5-zone models — and the smaller refinements that came with them.

Anaerobic Speed Reserve (ASR)

The headline feature is the ability to determine an athlete’s anaerobic speed reserve — the velocity range that sits between the speed at maximal oxygen uptake (vVO2max, or maximal aerobic speed) and maximal sprinting speed (MSS). Everything an athlete does above their aerobic ceiling happens inside this band, which is exactly why it matters for events decided by surges, kicks and repeated high-intensity efforts.

The concept owes much to the work of Dr Gareth Sandford and colleagues, who showed that ASR and maximal sprint speed are “untapped tools” for differentiating the world’s best middle-distance runners and for understanding the complexity of athlete profiles that traditional aerobic categories miss. Two athletes with an identical vVO2max can have very different reserves above it — and therefore very different tolerances to supramaximal work — information that is invisible if you only look at threshold and VO2max.

Dr. Martin Buchheit’s research extends this directly into programming. Prescribing high-intensity work as a percentage of maximal aerobic speed alone ignores the differing mechanical ceilings between individuals, so the same session can impose very different relative stress on two athletes. Anchoring supramaximal efforts to a percentage of the ASR instead normalises that stress, and the evidence shows it reduces the inter-individual variability of physiological adaptation. The app now makes that calculation a single step rather than a spreadsheet exercise.

Maximum Speed Determination

Because ASR depends on having a reliable upper anchor, the app now supports maximum sprint speed (MSS) determination as a first-class input. Enter the result of a short maximal sprint and the app uses it as the top of the reserve, pairing it with the aerobic anchor derived from the step test. This closes the loop: from a single profiling session you get the threshold values, the aerobic speed, the sprint ceiling, and the reserve that connects them.

Flexible Training Zones: 3 or 5

Training-zone prescription is now configurable. You can choose between a 3-zone model — the classic below-LT1, between-thresholds, above-LT2 structure favoured in polarised approaches — and a more granular 5-zone model for coaches who want finer resolution across the intensity spectrum. Zones are generated directly from the athlete’s own threshold and speed anchors rather than from generic percentages, so the prescription reflects the individual profile the test produced.

Switching between the two models takes a tap, which makes it easy to align the output with whichever periodisation philosophy a given athlete or training block calls for.

Other Improvements

Alongside the marquee features, this round of work brought a number of refinements: cleaner presentation of the threshold detection results, a more consistent workflow from data entry through to zone output, and better handling of the speed-based inputs that the ASR and MSS features rely on. The aim throughout has been to keep the app fast to use rink-side or track-side while quietly adding depth for those who want it.

Development is ongoing, and I’ll keep posting updates here as new capabilities land. If you’re using the app and have feedback or feature requests, I’d be glad to hear them. If you use it for any purposes make sure you reference it:

Cardinale, M. (2026). Lactate Threshold and HIT designer [Web application]. Retrieved from https://lactatethresholdhitdesigner.netlify.app.

⚠️ UPDATE 1st June 2026 ⚠️: I have now added the option for Cycling Tests.

A note for team-sport coaches: if you are specifically after a tool to plan HIIT sessions with change-of-direction (COD) prescriptions, I’d recommend Dr Martin Buchheit’s dedicated COD shuttle prescription app, available here. It is purpose-built for that use case and complements the profiling work the Lactate Threshold app is designed for. A screenshot is below.

Key References

  • Sandford GN, Allen SV, Kilding AE, Ross A, Laursen PB. Maximal Sprint Speed and the Anaerobic Speed Reserve Domain: The Untapped Tools that Differentiate the World’s Best Male 800 m Runners. Sports Medicine, 2019.
  • Sandford GN, Laursen PB, Buchheit M. Anaerobic Speed/Power Reserve and Sport Performance: Scientific Basis, Current Applications and Future Directions. Sports Medicine, 2021.
  • Buchheit M, Laursen PB. High-Intensity Interval Training, Solutions to the Programming Puzzle. Part II: Anaerobic Energy, Neuromuscular Load and Practical Applications. Sports Medicine, 2013.
High Intensity training, Intermittent Exercise, Repeated Sprint, Sports Science

High intensity interval training in health and disease

I have been reading in the last two days the very recent review from Martin Gibala on high intensity interval training (HIIT) and its effectiveness on health and disease. This is an excellent review paper which shows how effective this training modality is as well as how efficient it is, considering that gains can be obtained with a lot less time than conventional aerobic exercise modalities.

Considering the body of knowledge so far accumulated on the beneficial effects of high intensity exercise, sometimes I wonder why I still see team sports players spending precious training time on an athletics track running 1000 meters and above.

Evidence suggests that  when compared on a matched-work basis or when estimated energy expenditure is equivalent, HIT can serve as an effective alternate to traditional endurance training, inducing similar or even superior changes in a range of physiological, performance and health-related markers in both healthy individuals and diseased populations (Hwang et al 2011; Wisloff et al 2007).

Growing evidence suggests also that low volume HIT stimulates physiological remodelling comparable to moderate-intensity continuous training despite a substantially lower time commitment and reduced total exercise volume (Gibala & McGee 2008).

In fact, many authors found similar training-induced improvements than conventional endurance exercise in various markers of skeletal muscle and cardiovascular adaptation despite large differences in weekly training volume (~90% lower in the HIT group) and time commitment (~67% lower in the HIT group). In addition to an increased skeletal muscle oxidative capacity, other endurance-like adaptations have been documented after several weeks of low-volume HIT include an increased resting glycogen content, a reduced rate of glycogen utilization and lactate production during matched-work exercise, an increased capacity for whole-body and skeletal muscle lipid oxidation, enhanced peripheral vascular structure and function, improved exercise performance as measured by time-to-exhaustion tests or time trials and increased maximal oxygen uptake (Burgomaster et al., 2005; Burgomaster et al. 2008; Gibala et al. 2006; Rakobowchuk et al. 2008).

The protocols used are pretty similar. Here is a summary table.

Protocol

Reference
30 s “all out” × 4–6 repeats, 4.5 min rest. 3 sessions per week Burgomaster et al., 2005; Burgomaster et al. 2008
30 s  “all out” × 4–6 repeats, 4 min recovery. 3 sessions per weel Gibala et al. 2006
30 s “all out” × 4–6 repeats, 4 min recovery. 3 sessions per week Rakobowchuk et al. 2008

The results are of course pretty impressive and compare well with conventional endurance exercise.

In Burgomaster’s et al. study (2008), VO2peak increased after training, with no difference between groups (HIT vs. conventional aerobic (ET)). Peak power output elicited during the Wingate Test increased by 17% and 7% in the HIT and ET groups, respectively, with no difference between groups, whereas, mean power output was increased by 7% only in the HIT group. ET consisted of continuous cycling on an ergometer, 5 days per week (Monday–Friday) for 6 weeks, at a power output corresponding to ∼65% VO2peak. Subjects performed 40 min of exercise per training session for the first 2 weeks. Exercise time was increased to 50 min per session during weeks 3 and 4, and subjects performed 60 min of exercise per session during the final 2 weeks.

Time trial improved more in the HIT group (SIT in the figure below) when compared to the ET group (6 sessions of sprint interval training (SIT) or endurance training (ET) over 2 weeks). The ET group performed training consisted of 90–120 min of continuous cycling at an intensity corresponding to 65% of VO2peak. Training progression in the ET group was implemented by increasing the duration of exercise from 90 min during sessions 1 and 2, to 105 min during sessions 3 and 4, and finally to 120 min during sessions 5 and 6.

An external file that holds a picture, illustration, etc. Object name is tjp0575-0901-f1.jpg Object name is tjp0575-0901-f1.jpg

Considerable evidence currently exists to support a role for low-volume HIT as a potent and time-efficient training method for inducing both central (cardiovascular) and peripheral (skeletal muscle) adaptations that are linked to improved performance and health outcomes. However few things should be considered when prescribing training programmes involving high-intensity training.

1) HIT requires “all out” supramaximal efforts followed by low intensity efforts. If you prescribe a programme asking your athletes to sprint at “60% of their max” or anything like that, they are not performing high intensity interval work.

2) Maximal means “all out”, I see too many “interval sessions” with intensities below 100% of an athlete’s max.

3) Adequate recovery is needed and workloads planned should take into account the ability of the individual involved.

4) Heart rate and blood lactate monitoring will provide you with the necessary  information to be able to manipulate sets vs reps as well as recovery protocols, as well as giving you feedback on how your athlete/client is progressing.