Optimising Running Performance Through Smart Hydration: A Guide for Athletes | Find Your Stride | Edinburgh Podiatrist

Introduction

Hydration isn’t just about quenching thirst — it’s a performance tool. For runners, fluid balance affects biomechanics, muscle function, and even foot health. As sports podiatrists focused on helping athletes run farther, faster, and pain-free, we know that hydration plays a pivotal role in preventing soft-tissue fatigue, blistering, cramping, and overuse injuries. This article breaks down hydration strategies proven to improve performance, while keeping your feet and lower limbs strong through every stride.

Why Hydration Matters for Runners

Even mild dehydration can impact your run. Dehydration increases core temperature, heart rate, and perceived exertion — making the same pace feel harder. Research shows that losing more than ~2% body weight through sweat can degrade aerobic performance, especially in warm conditions  .

For runners, that means:

• Slower pace and reduced endurance

• Higher injury risk due to muscle fatigue

• Increased chance of heat-related illness

• Greater risk of foot swelling, blistering, and shoe irritation

Hydration also matters for foot biomechanics. Dehydrated muscles fatigue faster, altering gait mechanics and increasing load on key structures like the Achilles tendon, plantar fascia, and tibialis posterior — common sites of running injuries.

Sweat Rates Vary—Find Your Personal Hydration Needs

Sweat loss depends on temperature, pace, body size, and training status. Elite endurance athletes often see sweat losses between 0.5–2.0 L/hour  .

How to Calculate Sweat Rate

1. Weigh yourself before a run

2. Run 60 minutes

3. Weigh yourself again

4. Track fluids consumed

✏️Sweat Rate = (Pre-run weight − Post-run weight) + Fluids consumed. Aim to replace enough fluids to prevent >2% body-weight loss. Monitoring this regularly helps tailor hydration for different conditions.

Before Your Run

Goal: Start euhydrated — your system balanced, not over-filled. Evidence suggests hydrating 4 hours pre-run (~5–7 mL/kg), with another 3–5 mL/kg at 2 hours if urine remains dark  .

Podiatry-specific tip:

Slight sodium intake pre-run can reduce foot swelling and help maintain ankle stability by supporting neuromuscular control.

During Your Run

Drink to avoid >2% body-weight loss. Many runners perform well consuming:

~0.4–0.8 L/hour depending on pace, size, and heat conditions  .

Consider taking on electrolytes and carbs if you are:

Running >60 minutes

Training in heat

Doing speed or race-pace efforts

Sodium improves fluid retention and thirst response, while 30–60g carbohydrate per hour helps maintain pace and reduce fatigue-related gait changes  .

After Your Run

Rehydrate Strategically - Drink ~1.5 L fluid per kg lost to fully replenish hydration stores  .

Pair fluids with salt intake and recovery nutrition to speed rehydration and reduce muscle soreness, tendon stress, and lower-limb fatigue.

Hydration Mistakes Runners Make

Starting dehydrated - raises injury + heat-stress risk

Drinking only water for long runs - can cause hyponatremia

Ignoring sweat rate - under or over-hydration

Relying only on thirst - thirst lags behind dehydration

Over drinking is dangerous — it’s a leading cause of exercise-associated hyponatremia in endurance events.

Final Thoughts

Hydration isn’t just fuelling — it’s a iperformance too an injury prevention too.

By staying optimally hydrated, runners maintain efficient biomechanics, stable foot function, and peak performance. Measure your sweat rate, hydrate strategically, and support your feet on every training mile.

Citation

Sawka, M. N., Burke, L. M., Eichner, E. R., Maughan, R. J., Montain, S. J., & Stachenfeld, N. S. (2007). Exercise and fluid replacement. Medicine & Science in Sports & Exercise, 39(2), 377–390. https://doi.org/10.1249/mss.0b013e31802ca597

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