Dawn Of The Data
In an age when every amateur can measure power and heart rate, the pros are going several steps further in the hunt for a competitive edge. Welcome to the world of internal heat monitors, glucose tracking, muscle wands and sweat profiles
The ever-intensifying search for marginal gains has seen pro racing teams embrace a raft of new body monitoring tech – and it could help you too
For a team more suited to one-day Classics, DeceuninckQuickstep had a very successful Giro d’italia. The Belgian squad’s 22-year-old Portuguese rider, João Almeida, clung on to the race leader’s jersey for 15 consecutive days after slipping into pink on Stage 3 with a strong showing on the climb to Mount Etna. By the end of the Tour DeceuninckQuickstep were the only team to have three riders in the top 15, including Almeida in fourth, Fausto Masnada in ninth and British rider James Knox in 14th.
An indicator of the kind of performance required to succeed at a major race came after the stage to Etna, when Masnada and Knox published some of their stats for the public to pore over. On the 18.6km, 6.7% climb Masnada topped out in 48 minutes 28 seconds at an average heart rate of 172bpm, fuelling an average power output of 348 watts. Knox fell 15 seconds short of his teammate’s time, his eye-opening 184bpm resulting in an average 333 watts.
It makes for interesting reading but it’s the kind of data that’s standard fare for any cyclist with a Strava account. What the stats don’t tell us is how hot the riders got as they powered up Etna’s slopes. And this is where the next wave of metrics comes in, with pro teams looking to monitor all aspects of a rider’s physiology with a view to adapting training regimes and diets in the name of those all-important marginal gains.
In Italy an unnamed Deceuninck-quickstep rider rode every stage of the Giro with a device monitoring his core body temperature clipped to a heart-rate strap. On that Etna stage the unknown rider saw his core start the day in Enna at 37°C before hitting 39°C atop the active volcano 150km later. Fire meets fire.
Similarly, French company Bodycap has developed an e-pill that monitors body temperature from the inside after it has been swallowed. It contains a temperature sensor, radio frequency antennae, four batteries and a processor, wrapped in a PVC shell. Once in the gastrointestinal tract the e-pill can relay data every 30 seconds to a laptop.
But is it useful? ‘Yes,’ says Bodycap’s Sebastian Moussay. ‘Measure the core and you can track correlations between temperature and performance. This is even more important in extreme environments and can help guide hydration and clothing strategy.’ It’s also useful to measure how well a rider is acclimatising to the heat, which can determine training intensity and help a sports director look after their riders during a race.
‘One time a rider from FDJ had a core temperature that was over 39°C even before the warm-up,’ says Moussay.
‘On the stage it tipped over 40°C. He had to quit the race.’
The Bodycap e-pill can’t offer on-the-fly feedback – it can’t interface with a phone or bike computer – although that’s something the French company is discussing with sports-tech companies. But Moussay says the development of swallowable monitors could open up a swathe of further metrics of value to coaches. ‘For example we’re looking at ph feedback. Acidity is another limiter and it could provide useful information on specific training loads and sustainable race power output.’
Tapping the fuel gauge
It wasn’t just Deceuninck-quickstep trying out new body monitoring tech at the Giro d’italia. Ineos Grenadiers and Jumbo-visma both used a glucose sport biosensor called Abbot Libre Sense, which is a small disc worn on the back of the upper arm. A thin filament inserted just under the skin measures glucose levels in the body, and the biosensor then relays that information to the Supersapiens app.
Glucose is nectar when it comes to cycling – elites can store around 500g in the form of glycogen, recreational riders more like 300g – so the benefits of being properly fuelled heading into a decisive Alpine climb or prepping for a breakaway are clear. And when every athlete responds differently to the amounts and types of nutrition they consume, it makes sense to monitor individuals and adjust their personal fuelling strategies accordingly.
Just how influential the glucose-monitoring tech was for Ineos Grenadiers at this year’s Giro is hard to conclude, since as press officer George Solomon concedes, ‘With the condensed season and lack of training time we haven’t widely used the product yet.’ But Sir Dave Brailsford is always one for ‘finding technological solutions for optimal fuelling and empowering riders’, and the British team has let slip that they have ‘used continuous glucose monitors in the past’.
Could one of those occasions have been on Stage 19 of the 2018 Giro d’italia, when Chris Froome defied 21st century cycling logic to execute a race-winning 80km solo break? We’d heard rumours that Team Sky (as they were then) had formulated a very specific fuelling plan on that stage, which led to all spare hands being drafted in – mechanics, press officers, security guys – to hand Froome nutrition at 10-minute intervals on the hourlong climb of the Colle delle Finestre. Ineos won’t say for sure, but perhaps Froome’s escape to victory was plotted via his specific blood-glucose data.
Certainly we can expect to see the telltale circular bump beneath a rider’s jersey sleeve more frequently as the drive for fuelling perfection continues.
The magic wand
How far ahead of the glucose curve Ineos Grenadiers are now is conjecture. What’s clearer is that Supersapiens has been building on the work of Dr Inigo San Millán, director of performance and health at UAE Team Emirates and a vital component in Tadej Pogačar’s remarkable Tour de France
Each day at the Tour Team Emirates’ Dr San Millán ran a handheld wand over Pogacar’s thighs, which would emit soundwaves in varying frequencies depending on water content
victory in September. For a couple of seasons now UAE Team Emirates have been using San Millán’s own Musclesound creation. Each day at the Tour, San Millán would run a handheld wand over Pogačar’s thighs, which would emit soundwaves in varying frequencies depending on water content (carbs absorb water, so more water means more glycogen).
‘On a screen we can then see either black – glycogenrich muscle – or white – glycogen-depleted,’ San Millán says. ‘An algorithm then calculates a “muscle energy status” score. If it’s too low we might need to load the rider up with carbs or tone down the training.’
These metrics have nestled in the labs for years. Now, with equipment lighter and more practical, they’re at training camps and races. Which, says San Millán, can pay dividends.
‘There’s a whole debate around whether riders need to eat more or less carbohydrates, with some giving it neardemonic status. With this muscle wand you can clearly show the rider whether their deposit is full or empty. Sometimes the rider thinks they need to eat a lot and the results suggest they’re actually at capacity. And that’s crucial because extra glycogen is converted into fat, which means more weight to carry up the mountains.’
Hydration matters
That data-driven assessment certainly paid off at this year’s Tour, where Pogačar dished out a time-trial beating to fellow Slovenian Primož Roglič. While one shed tears, the other drank champagne – a rare alcoholic interlude for the monastic peloton of the modern age. It wasn’t always thus.
The epic 580km Bordeaux-paris race saw many teams in the mid-20th century prescribe port, white wine, brandy and champagne. It was a bad call. Lose 2% of bodyweight from dehydration and your power output drops, decisionmaking crumbles and strength disappears. If dehydration escalates so too do the risks. A severely dehydrated Tom Simpson died on the slopes of Ventoux, as the Daily Mail reported, ‘slowly asphyxiated by intense effort in a heatwave after taking amphetamine and alcohol’.
Today’s riders are educated in all things hydration, with urine charts being the daily norm at races and training camps. At sweltering multi-stage races such as the Tour,
where roadside temperatures can reach 50°C, monitoring is even more important. So too is individualisation, say Team Sunweb. The German outfit, whose 22-year-old Swiss rider Marc Hirschi lit up the Tour, have spent the past season working with Precision Hydration, a Dorsetbased company that prescribes personalised hydration solutions based on its advanced sweat test.
‘It’s important because sweat contains salt, which contains sodium, so the more you sweat the more sodium you lose,’ says founder Andy Blow. ‘But the amount of sodium per litre of fluid can vary markedly by rider, from around 200mg to 2,000mg, though the average is 987mg.’
What causes this variation isn’t fully understood. The fact that low-sodium sweat is arguably more conducive to riding faster and longer in the heat suggests cyclists of, say, an African lineage would require less sodium. But Blow’s research doesn’t necessarily support this.
‘There’s a genetic component but to what extent we’re unsure. We also know everyone’s blood-sodium level is at around 3,600mg per litre and is regulated tightly so if you eat a high-sodium meal you’ll pee out a lot of salt.
Where we feel levels change is in the sweat gland. Ion reabsorption channels claim back some of the electrolytes because your body doesn’t want to lose all of its of salt.
That looks like it’s key. Some, like me, either lack the absorption capacity or just aren’t that efficient.’
It’s this insight that saw Sunweb sweat-testing their riders. The test involves strapping two electrodes to an arm, one of which contains a disc with pilocarpine gel, a medicine that makes the sweat glands produce sweat. It was first used on cystic fibrosis sufferers, who often sweat more with the sweat containing high levels of chloride.
‘It was revealing how each rider differed from stage to stage at the Tour,’ says Blow. ‘This depended on external factors like stage length and profile, weather and the rider’s role on the day. Across the team the lowest average fluid intake per hour was 250ml during Stage 1 [a flat, rainy 156km loop]; the highest 1,176ml during Stage 16 [164km, five categorised climbs and hot]. The lowest average sodium loss per hour was 128mg [Stage 1]; the highest 956mg [during the 191km sixth stage that ended with a cat-one climb].’
That wide salty bandwidth results in Blow prescribing a specific hydration product, ranging from a sodium low of 250mg to a peak of 1,500mg. The ideal is that the rider consumes this throughout the stage, but the reality is that a domestique isn’t going to drag himself through the peloton delivering bespoke bottles to every teammate. That’s why the actual hydration profile for a heavy sweater like Tiesj Benoot might look like one 500ml bottle of 1,500mg prerace, one 1,500mg bottle in the race, plus nine electrolyte capsules and seven 500ml bottles of generic isotonic.
Has it made a difference? The proof isn’t conclusive, but this year’s Tour was a revelation for Team Sunweb, seeing them rack up three stage wins, two seconds, three thirds, nine top 10s and the combativity award for Marc Hirschi.
Drowning in numbers
Monitoring a pro cyclist is big business, which is hardly surprising when a team’s prized asset might cost them upwards of €5 million a year. On top of all this tech teams will measure aerodynamic efficiency, haemoglobin levels (non-invasively, of course), sleep, stress and cortisol levels and plenty more. The danger is that for humans who already watch their every morsel, their every pedal stroke, this Big Brother approach becomes too intense.
That’s where the human touch comes in. Despite an increasing reliance on crunching numbers there will always be a place for an experienced DS – someone who knows the right balance between data and intuition. Get it right and, as Pogačar showed in France, success awaits. James Witts is a freelance journalist who prefers to chew his data rather than crunch it
‘Sometimes the rider thinks they need to eat a lot and the results suggest they’re actually at capacity. That’s crucial because extra glycogen is converted into fat, which means more weight’