Can Sodium Bicarbonate Help You Ride Faster at Altitude?

Sodium Bicarbonate at Altitude: What This Study Actually Shows

Moderate altitude already changes how hard efforts feel. At around 1,800 m, endurance athletes experience a measurable drop in performance during sustained high-intensity exercise. This is not only due to reduced oxygen availability, but also because fatigue-related acid–base disturbances develop more quickly in hypoxia.

A 2026 study published in the European Journal of Applied Physiology examined whether sodium bicarbonate, delivered in a specific form, could meaningfully influence performance under these conditions.

What the Study Did

Fourteen trained male cyclists completed 40 km cycling time trials in acute normobaric hypoxia, simulating an altitude of ~1,850 m. Ninety minutes before each trial, athletes ingested either:

0.3 g·kg⁻¹ body mass sodium bicarbonate, delivered as mini-tablets in a carbohydrate hydrogel, or
A matched placebo.

The design was randomized, double-blind, and crossover, ensuring that each athlete served as their own control.

What Was Found

Cyclists completed the 40 km time trial ~1.2% faster after ingesting sodium bicarbonate. This corresponded to an average improvement of ~45 seconds, alongside higher mean power output and speed across the full distance.

Notably, pacing strategy did not change. Athletes neither started harder nor faded differently, indicating that the improvement reflected a greater ability to sustain work rather than altered effort distribution.

Physiologically, sodium bicarbonate raised blood bicarbonate by ~4.8 mmol·L⁻¹ before exercise and maintained higher blood pH throughout the trial, reflecting an enhanced extracellular buffering capacity during prolonged high-intensity work in hypoxia. Blood lactate concentrations were also higher, consistent with greater sustained metabolic output.

Despite these changes, heart rate, oxygen uptake (VO₂), cadence, and perceived exertion were unchanged. Athletes produced more power without experiencing greater perceived or cardiovascular strain.

Gastrointestinal symptoms were minimal and comparable to placebo, suggesting good tolerance of this specific ingestion format.

Practical Implications for Endurance Athletes

Based on the evidence in this study, this suggests the following:

For time-trial–like efforts at moderate altitude (~1,800 m), sodium bicarbonate can provide a small but measurable performance benefit.
The benefit appears during prolonged high-intensity efforts (~1 hour), not short sprints or low-intensity work.
Performance improved without higher perceived effort, heart rate, or oxygen uptake, indicating improved tolerance rather than increased strain.
Pacing behavior was unchanged, so the benefit does not rely on racing differently.
Gastrointestinal tolerance was good when sodium bicarbonate was delivered as mini-tablets in a carbohydrate hydrogel.

Equally important, this study also implies:

The advantage is modest and best viewed as a marginal gain, not a transformation.
The findings apply only to trained male cyclists under acute hypoxic conditions.
This does not establish optimal dosing strategies beyond the tested protocol, nor does it guarantee similar effects in other sports or populations.

Bottom Line

In trained male cyclists performing a 40 km time trial in acute hypoxia, sodium bicarbonate delivered as mini-tablets in a carbohydrate hydrogel improved performance by ~1.2%, with minimal gastrointestinal symptoms and no increase in perceived effort.

For endurance athletes competing or training at moderate altitude, this study suggests that buffering capacity—rather than oxygen delivery—can meaningfully influence sustained high-intensity performance, within clearly defined and limited bounds.

Source: https://link.springer.com/article/10.1007/s00421-025-06069-6