The parcours of the 2023 Giro d’Italia covers 3,448.6km from the Grande Partenza in Abruzzo to the finish line in Rome. In that time the riders will climb a total of 51,300m that includes three stages that consume more than 5,000m apiece. It begs two questions: is race director Mauro Vegni a bonafide sadist? And, of course, for the purposes of this feature, what does science say about when the climbers should remain seated on their saddles or ease up and stomp on the pedals?
Climbing under the microscope
The body’s a complex organism. While the motion of the legs is somewhat constrained during the pedalling motion because the feet are fixed to your pedals, a change in cycling position catalyses a series of changes throughout the kinetic chain that either activates or deactivates muscles. This affects maximal power output as well as the physiological response, including oxygen uptake and heart rate. It’s hammered home by manufacturers and media alike home how a change of body position affects aerodynamics, drag and whether you scythe through the air (relatively) friction-free or mimic a billowing parachute, but your position also affects energy expenditure and, of course, speed.
In 2008, Ernst Hansen and Harry Waldeland of the Norwegian School of Sport Sciences undertook an experiment to quantify whether seated or standing was optimal for intense uphill efforts. They recruited 10 male second-category riders. They had an average age of 27, measured 1.82m tall, weighed 75.2kg and enjoyed an impressive VO2max of 70ml/kg/min. They reported to the Norwegian lab six times over a three-week period.
Test one was simply about becoming familiar with the motorised cycling treadmill. Test two involved cycling in the seated position at an average 17.8km/hr with gradient set at 5.8% so the riders could achieve a power output of around 3.5 watts per kilogramme. As each minute ticked by, the gradient increased by 0.8% until volitional exhaustion; in other words, they could cycle no more. They rested for 90 minutes and then repeated the agony in the standing position.
The next four test days were broadly similar, albeit gradient was fixed at a cruel 10%. By now, the speeds were individualised but power outputs were the same across the board, each subject targeting 86%, 96%, 118% and 165% of their max. They rode this both seated and standing. Throughout the torturous experiment, the scientists analysed heart rate, blood lactate and pulmonary gas exchange.
Once the sweat had dried, pin pricks had healed and the cyclists were no longer breathing out of their chamois, what did they discover? One of the key findings, say the authors albeit perhaps not surprising to road riders, was that climbing at a gradient of 10% at a power output of 165 watts could be sustained longer in a standing position than a seated cycling position.
“The reason why performance was better during standing cycling at the highest power output could be biomechanical differences between seated and standing cycling that allow the cyclist to sustain standing cycling at such a power output,” the study read.
“The arms pull up and back during the power stroke of the corresponding leg during standing cycling, while they push down and forward during the upstroke of the corresponding leg. In as much as these arm activities are co-ordinated with the leaning of the bicycle, the arms contribute with positive power output. At the same time, body mass is used more actively during standing than seated cycling, as the hips are further forward and provide a leverage over the crank arm different from that experienced in the seated position.”
Steep out, shallow in
So, all good, when the hills rise, so should you. Of course, it’s not as simple as that with the authors noting that the biomechanical characteristics of standing cycling increase oxygen uptake and energy expenditure compared to seated cycling. But, all in all, for short bursts at 10% or more, ease off your saddle and push on.
The authors then sent us to another study that showed seated pedalling proved more efficient at gradients of 4% with oxygen uptake 10% lower. So, the numbers say what we suspect: stay seated on shallow gradients, ease out of the saddle when the climb stiffens.
When it comes to the 2023 Giro d’Italia, on paper the leading riders will spend much of the penultimate stage out of the saddle and arguably on road bikes rather than TT alternatives (or maybe even swapping between the two). Although the first 11km of 18km time trial from Tarviso to Monte Lussari Tudor are relatively flat, the first 5km of the Monte Lussari climb are an average 15%, peaking above 20%. Even the canopy of trees that shelter this section of road will fail to mask the pain on the riders’ faces. Past the woods, the gradient falls to 4% for a short stretch before a short ramp in the final kilometre where the gradient reaches 22%. A short descent is followed by a double bend and then a pitch of 16% for the last 150m.
It's brutal and will have been recced by all of the leading contenders and their teams. But for the backroom staff, arguably they’re more concerned by the gradient impact on power output than the steepness itself.
“There are few studies that directly compare efficiency and economy between seated and standing positions in well-trained cyclists, let alone WorldTour cyclists,” says Elliot Lipski, coach at Alpecin-Deceuninck. “However, of the evidence that we do have to go by, there is a negligible difference between both efficiency and economy between seated and standing positions at powers typically produced on climbs. A study from 2002 looked to investigate this and found no differences between seated (flat), seated (climb) and standing (climb).
“What we do know is that the more time you spend working on something, the more efficient you will become at doing just that. World Tour cyclists complete upwards of five-million pedal revolutions per year, and it’s reasonable to say that the more time they spend in or out of the saddle will lead to individual differences in efficiency and technique.”
This marries with a conversation we had several years ago with the sadly passed Louis Passfield. Louis was an expert in this area – and an expert in the art of humanity; he was a lovely man – and, after many studies, came to the same conclusion: that if you cycle long enough and consistently enough, you’ll naturally fall into your perfect balance between seated and standing. Still, the support teams still offer guidance. Back to Lipski…
“At lower power output, I’d recommend to my riders to remain seated. This is because at wattage lower than around 75% of VO2max, economy drops when out of the saddle, most likely because the contribution of the extra work from the upper body accounts for a greater proportion of the total work produced.
“Generally speaking, pros will alternate between seated and standing positions to maintain a constant speed; efficiency is generally better at a steady state than it is with surges in power. So, alternating cadence and tangential force to match the gradient and speed on the climb will help them maintain their speeds. Also, when climbing out of the saddle, the riders tend to time their breathing with the cadence and rhythmic movement of the bicycle. This doesn’t seem to affect their efficiency but helps to control breathing frequency and heart rate.”
As you’d expect, there’s a weight component to all of this and is why Hansen’s study doesn’t directly relate to WorldTour riders, the contenders for the Giro anyway. The 10 subjects averaged 75kg compared to the following quartet: Remco Evenepoel 61kg; Tao Geoghegan Hart 61kg; João Almeida 63kg; and Primož Roglič 65kg.
In general, science would argue that “heavier” riders will look to remain seated longer as it’s biomechanically more efficient to support their load on a saddle than out of it, while lighter riders won’t be penalised so harshly when it comes to energy expenditure, which is arguably why sub-60kg Quintana in his pomp often climbed like his saddle was on fire.
Power-to-weight ratio can impact position choice, too. Around 6.4 watts per kilogramme is podium potential, though that’s based on the functional threshold. Most teams will have their riders’ figures for 30-minute climbs, 40 minutes… and also figures from one-minute bursts to 10 minutes for short, punchy climbs. In Hunter Allen and Dr Andrew Coggan’s book Training and Racing with a Power Meter, the authors include a table of data that illustrates world-class power-to-weight ratio figures across the board. As an example, functional threshold is given as 6.4w/kg, which increases to 11.5 watts/kg for one minute and 24.04 watts/kg for five seconds.
This is important when understanding the physics of a climb and a rider’s potential. That’s why you find bigger riders prefer longer, shallower gradients. The shallower it is, the less important power-to-weight is (relatively) and the more important CdA (coefficient of drag) is. So riders like Wout van Aert may love planting their buttocks on the saddle for long and shallow ascents because they’re pretty aerodynamic for the amount of power they can put out. Steeper, on the other hand, means slower and aerodynamics is less important, which is why smaller guys might ease out of their saddles and ride away.
Slow- and fast-twitchers
Muscle type makes a difference to which climbs a rider might prefer. If the rider has a prevalence of fast-twitch fibres, for example, they can generate high amounts of power in short periods of time, so might perceive out-of-the-saddle efforts on shorter, sharper climbs as more “pleasant”. These fibres fatigue faster but they’d enjoy recovery time between climbs. A rider packed with slow-twitch muscle fibres might “enjoy” the in-saddle long, shallower climbs.
This is important for many reasons including race selection and training content as well as influencing cadence choice. Unless you’re using a really low cadence with high resistive forces being generated, you’re unlikely to recruit a high proportion of type two fast-twitch fibres. Therefore, when climbing with a higher cadence you will be recruiting mostly type one and minimising recruitment of type-two fast-twitch fibres. With less reliance on type-two fibres, there’s a decreased likelihood for the onset of premature metabolic acidosis (the burn). Hence, why most WorldTour climbers tend to choose a high cadence when climbing rather than trying to grind it out.
Whose technique will rule in the Giro? Ultimately, the climber who knows thy body and technique best will be the one wearing the maglia rosa on Sunday May 28 2023.