In 2018, a study was published in the Journal of Sport Sciences that compared seated and standing cycling during outdoor time trials. They selected 13 elite cyclists and established their VO2max, which was on average 79,8 mL/kg/min, and maximal aerobic power, which was 6.3 W/kg. Each of them was asked to do 3 self-paced time trials on a 3-km-long climb with an average 7% gradient. They had 30 minutes to recover between each of their 3 rides. They were free to sit or stand during the climb as they wanted. Each of them was equipped with a power meter and portable analyser to collect metabolic and other physiological variables such as oxygen uptake or heart rate. The researchers followed the cyclists in a car from which they marked when the cyclists changed from seated to standing and for how long. Most of what the researchers found was as expected, cadence decreased when standing while the torque and power output increased. But there were a few surprises.
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• Cyclists spent 22,4% of the climb standing.
• The speed did not differ between seated and standing climbing positions. This suggests that they used standing to maintain speed during steeper parts of the climb.
• The longer they spent standing, the lower their cadence got. This suggests that standing for too long is more demanding.
• Their metabolic measures such as VO2 and heartrate HR did not differ between seated and standing climbing positions.

It is important to note that the time trial took fewer than 6 minutes and only the last 4 minutes of climbing were analysed. Changes in VO2 and heart rate might not be noticeable in this short time trial but it doesn’t mean that changes would be noticeable in longer climbs.

Cyclists regularly change from a seated to a standing position when the gradient increases during uphill cycling. The aim of this study was to analyse the physiological and biomechanical responses between seated and standing positions during distance-based uphill time trials in elite cyclists. Thirteen elite cyclists completed two testing sessions that included an incremental-specific cycling test on a cycle ergometer to determine VO2max and three distance-based uphill time trials in the field to determine physiological and biomechanical variables. The change from seated to standing position did not influence physiological variables. However, power output was increased by 12.6% in standing position when compared with seated position, whereas speed was similar between the two positions. That involved a significant increase in mechanical cost and tangential force (Ftang) on the pedal (+19% and +22.4%, respectively) and a decrease (-8%) in the pedalling cadence. Additionally, cyclists spent 22.4% of their time in the standing position during the climbing time trials. Our findings showed that cyclists alternated between seated and standing positions in order to maintain a constant speed by adjusting the balance between pedalling cadence and Ftang.