Metabolic assessment · London
VO₂ Max Test in London
VO₂ max testing — graded exercise test with breath-by-breath analysis of oxygen and carbon dioxide
A VO₂ max test that measures carbon dioxide as well as oxygen, which is what turns it into more than a number. You get your aerobic ceiling, both ventilatory thresholds, your measured maximum heart rate, the training zones that follow from them — and, because both gases are recorded, which fuel you are burning at each intensity and where fat oxidation peaks.
- Price
- £200
- Duration
- Approximately 60 minutes
- Locations
- Liverpool Street · Marylebone
Your ceiling, the intensities below it, and what you are burning at each one.
Oxygen and carbon dioxide, measured breath by breath across a progressive protocol. Each output is described once: what it is, how it is captured, and what it changes about how you train.
01VO₂ maxYour aerobic ceiling — the most oxygen you can take up and use.
How we measure it
You wear a mask that analyses every breath you take. It records how much oxygen you use and how much carbon dioxide you produce, second by second, as the effort increases. Reported in ml/kg/min and L/min.
Why it matters
It tells you the size of your engine. If your oxygen uptake levels off near the end, that is a true maximum. If it does not, we report the highest figure reached and say so plainly rather than calling it a maximum.
02VT1 — first ventilatory thresholdThe ceiling of genuinely easy work.
How we measure it
The point where your breathing first steps up out of proportion to the effort. It shows in the gas data before you would notice it yourself.
Why it matters
This is the ceiling for easy running or riding. The most common thing we find is that easy sessions are being run above it, which quietly turns easy days into moderate ones.
03VT2 — second ventilatory thresholdThe hardest effort you can hold without progressive fatigue.
How we measure it
The second, sharper step up in breathing, further into the test. It marks where the effort stops being sustainable.
Why it matters
Tempo, threshold and interval sessions are set from here. Thresholds sit within a small range rather than at one exact number, and your report shows them that way.
04Measured maximum heart rateYour actual HRmax, not an age-based estimate.
How we measure it
Your heart rate is recorded throughout, so the highest figure is the one you actually reached — not one worked out from your age.
Why it matters
The usual 220-minus-age formula can be out by 10 to 20 beats for any given person. Every zone below is built on your real number instead.
05Training zonesHeart rate, and running speed or cycling power, for every zone.
How we measure it
Worked out from your own two thresholds and your real maximum heart rate.
Why it matters
You get zones in heart rate and in pace or watts, so you can use whichever your session needs. Pace and power are more reliable on hills, in heat, and in intervals too short for heart rate to catch up.
06Fuel use across intensitiesWhat you are actually burning, and where it changes.
How we measure it
The ratio of carbon dioxide produced to oxygen consumed — the respiratory exchange ratio — recorded at every stage. That ratio is what allows fat and carbohydrate use to be estimated rather than assumed.
Why it matters
This is the part an oxygen-only analyser cannot give you. It shows the intensity at which your fuel mix shifts decisively towards carbohydrate, which is a different question from where your thresholds sit and is often the more useful one for a long event.
07FatMaxThe intensity at which fat oxidation was highest on the day.
How we measure it
Calculated from the gas data across the protocol, and reported alongside the conditions it was measured in.
Why it matters
Useful for shaping lower-intensity work and for framing a fuelling conversation. It is one input among several: FatMax on its own does not determine how you should fuel a race, and it shifts with training status, prior food and the conditions of the test.
08Your reportReviewed on screen the same day, written version follows.
How we measure it
A one-page summary, your full gas data with both thresholds and FatMax marked, your substrate curves, and a table of your zones.
Why it matters
We go through it on screen before you leave, and the written version follows. It also flags the two or three numbers worth watching if you test again later.
This assessment measures the ventilatory thresholds from gas exchange. It does not include blood lactate sampling — that is what the Endurance Performance Profile adds at £300, measuring both threshold systems in the same protocol so they can be read against each other.
Your ceiling and the intensities below it, measured on the day — not predicted from your age or your race times.
Measured with
- KORR CardioCoach MAX — breath-by-breath gas analysis
- Treadmill or cycle ergometer — you test in the mode you train in
- Heart-rate strap — your real HRmax, recorded throughout
The appointment takes approximately 60 minutes from arrival to leaving.
- 01IntakeTraining history, current weekly load and your target event. The protocol and starting intensity are selected from this.
- 02SetupThe metabolic analyser is calibrated for gas and flow. Mask fitted and heart-rate strap applied.
- 03Progressive protocolIntensity increases in stages. Breath-by-breath data is recorded throughout. Early stages are comfortable.
- 04ReviewYour curve, thresholds and zones are reviewed on screen with you before you leave.
- 05Written reportThe full report follows by email with the complete data set, your zones and recommendations.
Who gets the most from this.
Suited to
- Runners and cyclists who train to a structure and want zones based on measured values
- Triathletes who need zones established separately for each discipline
- Athletes preparing for a specific event who want a baseline before the training block begins
- Athletes whose progress has flattened despite consistent training
- Anyone whose current zones were set from an age-based formula or a field test
- Athletes retesting to establish whether a block has produced measurable change
Less suited to
- Anyone not currently training to a structure — the zones will be accurate but there may be little to apply them to
- Athletes who want movement or force-production information, which this assessment does not cover
If you are unsure whether this or the Complete Athlete Profiling assessment fits what you want to understand, ask before booking.
Treadmill or bike
Choosing the mode.
Treadmill
Produces zones expressed in running speed alongside heart rate. Appropriate for runners, and for triathletes establishing their run zones.
Running recruits a large muscle mass and typically produces a higher VO₂ value than cycling in athletes who are not primarily cyclists.
Cycle ergometer
Produces zones expressed in cycling power alongside heart rate. Appropriate for cyclists, and for triathletes establishing their bike zones.
Power is measured directly, which makes cycling zones straightforward to apply to structured sessions and to an indoor trainer.
Zones do not transfer cleanly between modes. Test in the discipline you are training for. Availability of each mode is confirmed when you book.
Questions we get asked.
Fast for at least three hours before the appointment and arrive well hydrated — normal fluid intake through the day before is enough. Avoid intense training the day before: the assessment measures your response, and arriving fatigued measures fatigue. Wear the kit and footwear you train in, and if you are testing on the bike bring your own shoes and pedals if you use them. Anything else specific to your protocol is confirmed when you book.
The protocol is progressive: it begins at a comfortable intensity and increases in stages. Most of the assessment is not maximal. The final stages are hard, and the clearest VO₂ max value comes from reaching a genuine maximal effort, but the test can be stopped at any point.
Both ventilatory thresholds are established from the submaximal stages, so the assessment still produces training zones. What may not be established is a confirmed VO₂ max. If a plateau in oxygen uptake is not reached, the highest value recorded is reported as VO₂ peak rather than a maximum, and the distinction is stated in the report.
Yes. Heart-rate zones, and running-speed or cycling-power zones, are derived from your measured ventilatory thresholds and your measured maximum heart rate, rather than from an age-based formula or a percentage of an estimated maximum.
No. This assessment establishes the ventilatory thresholds from gas exchange, which needs no blood sample. Blood lactate sampling is part of the Endurance Performance Profile (£300), which measures both threshold systems in the same protocol. Where the ventilatory and lactate thresholds agree you can hold the result with more confidence; where they diverge, that difference is itself informative.
Yes. The protocol adapts to the intensity you can produce, and the resulting zones are individual either way. What matters is whether you intend to use the zones. If you are not currently training to a structure, the measurements will be accurate but you may have little to apply them to.
A 12 to 16 week interval allows enough training to have taken place for a change to be measurable. Retesting sooner tends to measure day-to-day variation rather than adaptation.
At UNTIL Liverpool Street, 280 Bishops Square, London EC2M 4RB, or UNTIL Marylebone, 1 Orchard Street, London W1H 6HJ. Both are by appointment.
Book VO₂ max testing.
- Price
- £200
- Duration
- Approximately 60 minutes
- Locations
- Liverpool Street · Marylebone
Where
- UNTIL Liverpool Street280 Bishops Square, London EC2M 4RB
- UNTIL Marylebone1 Orchard Street, London W1H 6HJ
Both sites operate by appointment. Your location is selected when you book.