Ever wondered how you might perform at an XC race? According to a new study you can predict your ability without pinning on a number.

Citation: po.st/XCPrediction

Sports scientists have combined results from a suite of tests to predict how a rider will do in a 100-minute XC course, and they are surprisingly accuraste. Despite all the variables over such a long and complex event, their forecast is spot-on to within two minutes. Here’s our DIY assessment – let us know how well it works for you.

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The MBR XC prediction game

1. Decision-making: Choosing the right line at speed is crucial. The scientists use a special video app to test reactions, but you can try your hand at a crude one online at po.st/ReactionTime. Or you could turn photos of mtb trails into flash cards and see how quickly you can flick through them, spotting the best route.

2. Get a grip: A strong hold on the bars will optimise bike control – elite riders can squeeze just over 50kg in three seconds. You’ve certainly got Popeye arms if you can crush a can of Red Bull – unopened.

3. Ramp it up: If you’ve got a turbo-trainer you should increase your workload by 40W every four minutes until you collapse, or your cadence falls below 70, whichever happens soonest. To get a sense of your body’s efficiency at using oxygen – known as VO2 max – without directly measuring it, keep a record of your times and your breathing up your least favourite really, REALLY long, steep climb.

4. Power profile: The scientists had a lab with a high-end turbo-trainer. You can use a bike computer to record how you do when sprinting to the absolute max over six, 15 and 30 seconds.

The best predictor of how you’re going to do in a 100-minute XC race is your VO2 max compared to your weight (plus the weight of your bike), the scientists confirm. The higher that figure, the faster you’ll race. Your power profile in sprints is also pretty helpful in refining the forecast. Finally, throw in a figure for how good you are at choosing the fastest line. Now, enter that race to verify your experiement.