Hyperhydration for Cyclists: Science-Backed Technique to Increase Efficiency within the Warmth

Dehydration is likely one of the greatest threats to peak biking efficiency—particularly in sizzling and humid circumstances. However what for those who may delay its results earlier than your experience even begins? Enter hyperhydration: a science-backed technique designed to extend your physique’s fluid reserves earlier than you hit the saddle. By combining sodium, glycerol, or each, hyperhydration can increase plasma quantity, scale back core temperature, and lengthen endurance. Whether or not you’re coaching in excessive warmth or racing with out frequent entry to fluids, this system might be the efficiency edge you’ve been lacking.

Everyone knows the adverse influence that being dehydrated can have on efficiency. If dehydration is unhealthy, then one potential could also be to begin hyperhydrated to delay dehydration? Right here’s a more in-depth take a look at the science, use purposes, and greatest practices.

Warmth coaching is rising in recognition amongst professional riders and novice cyclists alike. Whereas many athletes are acquainted with the advantages of warmth adaptation, like decrease core temperature and elevated sweat effectivity, few are conscious of a complementary technique: hyperhydration. This technique can present related physiological benefits and will offer you an edge when the temperature begins to float up.

What Is Hyperhydration?

Hyperhydration refers to growing complete physique water earlier than train. By doing so, athletes can tolerate a better fluid loss earlier than efficiency begins to say no. Nevertheless, for those who’re in a position to keep hydration throughout train (by retaining fluid loss below 2% of physique weight), hyperhydration gained’t supply a lot additional profit. It’s most helpful when the danger of dehydration is excessive—throughout lengthy, sizzling races or when fluid entry is restricted (1).

The advantages of hyperhydration overlap with these of warmth coaching, together with:

• Expanded blood plasma quantity
• Decrease coronary heart price
• Lowered core temperature
• Elevated time to exhaustion

To hyperhydrate successfully, athletes usually ingest sodium and/or glycerol with massive quantities of fluid. These substances assist the physique retain extra water than it could by ingesting water alone. Usually, the kidneys regulate extra fluid by growing urine output, however glycerol and sodium gradual this course of, permitting extra water to “stick” within the physique (1).

Glycerol: A Resurging Possibility

Glycerol is a three-carbon alcohol naturally present in some meals like soybeans and infrequently added to processed merchandise as a sweetener or thickener. It’s simply absorbed and distributed all through the physique. As soon as absorbed, glycerol concentrates close to kidney cells, limiting how a lot fluid is filtered out by urine. This implies your physique retains extra water, and the impact lasts for a number of hours, longer than plain water alone (2).

Between 2010 and 2018, glycerol was banned by WADA on account of issues it may masks blood doping by growing plasma quantity. Nevertheless, it was later faraway from the banned record after research confirmed minimal influence on blood markers like hemoglobin and hematocrit. Throughout its time on the record, sodium rose in recognition as a main hyperhydration technique.

Learn how to Use Glycerol

Glycerol is often bought as food-grade vegetable glycerin—a thick, clear liquid. To make use of it:

• Combine 1.0–1.2 g/kg physique weight of glycerol with 20–25 ml/kg of fluid
• Devour over a 60-minute interval, two hours earlier than train, which permits time to urinate any extra fluid.

Outcomes usually present round 39% fluid retention—about 500 ml of the 1,800 ml consumed by a 70 kg athlete (3,4).

Sodium: The Extra Possibility

Sodium additionally creates an osmotic impact like glycerol, but it surely has further energy: it stimulates hormones like antidiuretic hormone (ADH) and aldosterone, which additional promote water reabsorption within the kidneys. In research, sodium constantly outperforms glycerol for fluid retention, although each are considerably simpler than water alone.

Learn how to Use Sodium

• Drink 20–25 ml/kg of physique weight in fluid
• Embrace 3 grams of sodium per liter (equal to about 7.5 g of salt)

This strategy ends in roughly 60% fluid retention, or 1,100 ml of the 1,800 ml wanted for a 70 kg athlete (3,4).

Combining Sodium and Glycerol

Current analysis has proven that combining sodium and glycerol has additive results. In a single examine, fluid retention reached 77% when each have been used, in comparison with 60% for sodium alone and 39% for glycerol alone (4).

There’s additionally rising curiosity in sodium bicarbonate, generally used to buffer lactic acid throughout high-intensity train. As a result of it requires massive sodium and fluid doses, it might double as a hyperhydration software. One examine discovered that sodium bicarbonate elevated plasma quantity by 8.1%, in comparison with 5.9% from sodium citrate and a lower in a management group (5). This means a novel twin profit: buffering and hyperhydrating directly.

Proof of Efficiency Advantages

A latest systematic overview on hyperhydration methods utilizing sodium and glycerol confirmed that each are efficient in growing complete physique water. Whether or not this interprets right into a efficiency profit, nonetheless, relies on the context.

• 5 of seven research reported a big enhance in time to exhaustion
• 9 research discovered a discount in coronary heart price by 3–11 bpm throughout regular work
• Plasma quantity elevated by 6–9%
• Pores and skin temperature additionally dropped when plasma quantity rose

These adjustments recommend that hyperhydration could assist athletes keep efficiency within the warmth by decreasing cardiovascular pressure and enhancing thermoregulation.

When to Use Hyperhydration

Hyperhydration isn’t for each experience or each rider. It could not assist (and will even hinder) efficiency in cooler circumstances or hilly programs the place additional water weight is an obstacle. Nevertheless, it shines in particular situations:

• When fluid wants exceed what you may realistically drink. Instance: Sweating out 1.8 L/hr requires ingesting 1.3 L/hr over 4 hours—not straightforward.
• Coaching or racing in excessive warmth or humidity
• Restricted fluid entry, akin to distant programs or lengthy gaps between assist stations
• Again-to-back race days or coaching classes
• Restricted in-race ingesting, akin to in time trials or weight-class sports activities
• Poor thirst cues or low drive to drink throughout train
• Night races the place post-event hydration could disrupt sleep

Consider it like carb-loading for hydration: simply as topping up glycogen shops helps delay power depletion, hyperhydration helps delay dehydration.

Cautions of Hyperhydration

Hyperhydration isn’t risk-free. Some athletes could expertise GI misery, nausea, or diarrhea. And naturally, added physique weight from retained fluids could also be an obstacle relying on the course profile. Like every diet or efficiency technique, it ought to be examined in coaching earlier than race day.

Hyperhydration might not be mainstream, but it surely’s a well-supported technique with clear physiological advantages when used appropriately. For cyclists tackling lengthy, sizzling, or logistically difficult occasions, it might be the important thing to staying cool, sturdy, and forward of the peloton.

References 

1. Jardine, W. T., Aisbett, B., Kelly, M. Okay., Burke, L. M., Ross, M. L., Condominium, D., Périard, J. D., & Carr, A. J. (2023). The Impact of Pre-Train Hyperhydration on Train Efficiency, Physiological Outcomes and Gastrointestinal Signs: A Systematic Overview. Sports activities drugs (Auckland, N.Z.), 53(11), 2111–2134. https://doi.org/10.1007/s40279-023-01885-2
2. Goulet, E. D., Aubertin-Leheudre, M., Plante, G. E., & Dionne, I. J. (2007). A meta-analysis of the results of glycerol-induced hyperhydration on fluid retention and endurance efficiency. Worldwide journal of sport diet and train metabolism, 17(4), 391–410. https://doi.org/10.1123/ijsnem.17.4.391
3. Savoie, F. A., Dion, T., Asselin, A., & Goulet, E. D. (2015). Sodium-induced hyperhydration decreases urine output and improves fluid stability in contrast with glycerol- and water-induced hyperhydration. Utilized physiology, diet, and metabolism = Physiologie appliquee, diet et metabolisme, 40(1), 51–58. https://doi.org/10.1139/apnm-2014-0243
4. Goulet, E. D. B., De La Flore, A., Savoie, F. A., & Gosselin, J. (2018). Salt + Glycerol-Induced Hyperhydration Enhances Fluid Retention Extra Than Salt- or Glycerol-Induced Hyperhydration. Worldwide journal of sport diet and train metabolism, 28(3), 246–252. https://doi.org/10.1123/ijsnem.2017-0310
5. Siegler, J. C., Carr, A. J., Jardine, W. T., Convit, L., Cross, R., Chapman, D., Burke, L. M., & Ross, M. (2022). The Hyperhydration Potential of Sodium Bicarbonate and Sodium Citrate. Worldwide Journal of Sport Vitamin and Train Metabolism, 32(2), 74-81. Retrieved Jul 29, 2025, from https://doi.org/10.1123/ijsnem.2021-0179

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