The lactic acid myth and the real science of buffering high-intensity fatigue

Demolishing the lactic acid myth

For decades lactic acid was blamed for muscle burn, fatigue and next-day soreness. Modern physiology has overturned almost all of this. Lactate itself is not a waste product — it is a usable fuel the heart and muscles oxidise for energy, and it is actively shuttled between tissues. It does not cause delayed soreness, which is driven by micro-damage and inflammation. The lactic acid story is one of the most persistent myths in sport.

What actually causes the burn

The burning sensation and force loss during very high-intensity effort are driven primarily by the accumulation of hydrogen ions and the resulting drop in muscle pH — the muscle becoming more acidic. This acidosis interferes with contraction and the enzymes that produce energy. Lactate production coincides with this process but is not the cause; the two were historically conflated. The real limiter is hydrogen ion accumulation, not lactate.

Buffering: raising the body's defence

Since the limiting factor is rising acidity, raising the body's buffering capacity allows higher intensity to be sustained for longer before pH drops critically. The body uses bicarbonate as one of its primary buffers. Increasing available bicarbonate gives the muscles more capacity to neutralise the hydrogen ions produced during intense efforts — directly addressing the actual mechanism of high-intensity fatigue.

Sodium bicarbonate: a proven ergogenic aid

Sodium bicarbonate is among the small number of sports supplements with strong, repeated evidence for improving high-intensity performance. It works by increasing extracellular buffering capacity, helping clear hydrogen ions from working muscle. The benefit is most pronounced in efforts lasting roughly one to ten minutes at high intensity — the range where acidosis is the primary limiter. A dedicated formula like Keforma's Ultra Bicarbonate is built specifically for this buffering purpose.

Who benefits and in which events

The athletes who gain most are those in middle-distance and repeated high-intensity disciplines: 400m to 1500m running, 100m to 400m swimming, rowing, combat sports and team sports with repeated sprints. For these events, where the burn of acidosis is the wall athletes hit, improved buffering can translate to measurable gains. For pure strength singles or long slow endurance, the effect is smaller.

The gut tolerance problem

The classic drawback of sodium bicarbonate is gastrointestinal distress — bloating, cramps, nausea — if taken incorrectly. This is managed through appropriate dosing, taking it with sufficient fluid and a little carbohydrate, timing it adequately before competition, and crucially practising it in training before ever using it on race day. Formulations designed for buffering aim to improve tolerability over crude baking soda.

Combining buffering with other strategies

Bicarbonate buffering pairs logically with beta-alanine, which raises intramuscular carnosine for intracellular buffering — the two work on different sides of the cell membrane and are complementary. Together with creatine for short maximal efforts, an athlete can address multiple fatigue mechanisms across the energy-system spectrum. Buffering is the specific tool for the acidosis-limited middle zone that neither creatine nor pure endurance fuelling addresses.