Stop Guessing.
Start Training With Data.

Any runner who wants to train smarter — from 5K improvers to marathon runners. Whether you're chasing a PB or returning from a break, knowing your real zones is the foundation of effective training. You don't need to be fast, just willing to push yourself in the test.

The Standard Assessment (£75) measures your VO₂max, Threshold and Critical Speed using a metabolic cart — breathing into a mask while running on a treadmill. The Full Lab Assessment (£125) adds blood lactate sampling at each stage, which pinpoints your LT1 and LT2 thresholds with greater precision. Both give you personalised zones, a training block, and 12 months of Run Pace Pal access. The Full Lab is ideal if you want the most accurate threshold detection.

Allow 60-90 minutes total. The actual running part is typically 20-40 minutes (incremental treadmill protocol to exhaustion), with time before for setup and calibration, and after for cool-down and initial results discussion.

Critical Speed (CS) is the fastest pace you can sustain without accumulating fatigue. Combined with your threshold data, it gives us a complete picture of your sustainable capacity. We use threshold and CS as the anchor points for all your training zones because they're more reliable than heart rate alone and reflect your true physiology. Every training pace is built from these markers.

You can continue at £19.99/month, or retest at £99 — which renews your data and extends your access by another 12 months.

Yes! The test starts at a very easy walking pace and gradually increases. You go at your own level — the protocol adapts to you. It's just as valuable for a beginner wanting to train effectively as it is for an experienced runner chasing a PB.

The test is treadmill-based at Box Nutrition's lab in Birmingham. This allows precise speed control and accurate metabolic measurements using the metabolic cart and lactate analyser. Your results translate directly to outdoor paces — we factor in the treadmill-to-road conversion.

You can cancel or reschedule your booking up to 48 hours before your test for a full refund. Cancellations within 48 hours may incur a fee. Contact us at info@boxnutrition.co.uk to make changes.

The test involves maximal exertion. If you have any heart conditions, respiratory issues, or other medical concerns, please consult your GP before booking. You'll complete a health screening questionnaire before testing. Box Nutrition's team are qualified sports scientists with first-aid certification.