Incremental Treadmill Running Test: Protocol, VO2max, and Ventilatory Thresholds

The incremental treadmill running test is the gold-standard lab assessment for evaluating a runner's endurance: it's flexible, controllable, and reproducible, and (when paired with gas analysis) it gives you real VO2max, ventilatory thresholds, and maximal aerobic speed (MAS) — three key numbers for designing high-quality training plans.

What does this test measure?

It measures the cardiorespiratory response to a progressively increasing effort on the treadmill, identifying:

• VO2max: maximal oxygen uptake (measured directly via cardiopulmonary exercise testing, or estimated from time/speed reached)
• Maximal aerobic speed (MAS): the speed at which VO2max is reached, key for programming interval sessions
• Ventilatory thresholds (VT1/VT2): when gas analysis is available, these mark the transitions between intensity zones

Equipment needed

• A treadmill that allows controlled increases in speed and/or incline
• Heart rate monitor
• Optional but recommended: a gas analyzer (cardiopulmonary exercise testing) for direct VO2max and ventilatory thresholds
• Borg scale for perceived effort

Protocol

1. Warm up for 10 minutes at low intensity on the treadmill itself
2. Define an incremental protocol: for example, a starting speed of 8-10 km/h (adjust based on level) with 1 km/h increases every 1-2 minutes, keeping the incline at 1% (to simulate outdoor air resistance)
3. At each stage, record: speed, heart rate, perceived effort (Borg) and, if equipment is available, VO2, VCO2, and respiratory exchange ratio
4. The test ends at voluntary exhaustion or when the subject can no longer maintain the speed despite repeated warnings
5. Identify:

- VO2max: the highest value recorded (or estimated from final speed/time) - MAS: the last fully completed speed stage (or interpolated based on time sustained in the final stage) - VT1/VT2: inflection points in the VO2/VCO2 relationship, if gas data is available

Common mistakes

• Increments that are too large (poor resolution for detecting thresholds) or too small (an excessively long test, where accumulated fatigue distorts results)
• Not standardizing incline between tests (affects MAS comparisons)
• Stopping the test too early out of caution, without truly reaching maximal effort

How to interpret the results

Reference table for MAS (km/h) by runner level:

Level	MAS men (km/h)	MAS women (km/h)
Recreational	12-14	11-13
Intermediate (club runner)	14-17	13-15
Advanced	17-19	15-17
Elite	> 19	> 17

MAS is especially useful because it lets you program interval sessions as a percentage of MAS (e.g., intervals at 90-100% MAS for VO2max work, 80-85% for threshold work), in a much more individualized way than relying on absolute paces alone.

Relationship with other tests

This test is the lab "common trunk" from which many field-based estimates are derived:

• Cooper Test (12 minutes) — an equivalent field estimate when treadmill or gas analysis isn't available
• Ventilatory threshold test — if gas analysis is available, this is obtained from the same incremental test

Plan your intervals with Movalytics

Once you have a runner's MAS and thresholds, the important part is making sure that data is available when you design their training plan. With Movalytics you can store the full results of the incremental test (VO2max, MAS, max heart rate, thresholds if available) in the athlete's profile, and pull them up anytime to fine-tune their interval paces.

Frequently asked questions

Do I need a lab to run this test? Not strictly: with a good treadmill and a heart rate monitor you can obtain MAS and max heart rate. Gas analysis (real VO2max, ventilatory thresholds) does require specific lab equipment. How is MAS used in practice? It's used as a percentage-based reference for programming intervals: for example, 3-5 minute repetitions at 95-100% of MAS to improve VO2max, or long runs at 70-75% to build the aerobic base. How often should this test be repeated? Every 8-12 weeks, ideally at the start and end of a training block, to recalibrate training speeds to the athlete's new fitness level.