Heatwaves, Hydration & Your Body

As temperatures rise during a heatwave, many people notice they feel more tired, stiff, achy, or even dizzy, but few realise just how much dehydration can affect the body, muscles, and joints.

At FYB, we often see an increase in muscle tightness, cramping, headaches, fatigue, and flare-ups of joint pain during hotter weather. Whether you’re training hard, working outdoors, or simply trying to stay active, hydration plays a huge role in how your body moves and recovers.

How Heat Affects the Body:

When the body gets hot, we sweat more to help regulate temperature. Alongside water, we also lose important electrolytes such as sodium, potassium, and magnesium. If these aren’t replaced, it can lead to:

• Muscle cramps and spasms
• Increased fatigue
• Reduced coordination and balance
• Headaches and dizziness
• Stiff joints and increased aches
• Reduced exercise performance
• Slower recovery after activity

Dehydration can also affect circulation and tissue elasticity, meaning muscles and connective tissues may feel tighter and more vulnerable to strains or injury.

Why Hydration Matters for Muscles & Joints:

Muscles are made up of around 75% water, meaning hydration is essential for proper muscle function. When dehydrated, muscles fatigue quicker and are more prone to tightness and cramping.

Joints also rely on fluid for lubrication and shock absorption. Poor hydration may contribute to increased stiffness and discomfort, especially in those already dealing with arthritis, chronic pain, or previous injuries.

For people undergoing physiotherapy, osteopathy, sports massage, or rehabilitation, staying hydrated can support:

• Better tissue mobility
• Improved recovery
• Reduced muscle soreness
• Improved circulation
• Better exercise tolerance

Signs You May Be Dehydrated:

Keep an eye out for:

• Dark yellow urine
• Dry mouth or headaches
• Feeling unusually tired
• Muscle cramps
• Dizziness when standing
• Increased stiffness or aches

If you’re exercising in the heat, these symptoms can come on quicker than expected.

Tips to Stay Hydrated During a Heatwave:

• Drink water consistently throughout the day, not just when thirsty
• Increase fluids if exercising or spending time outdoors
• Include electrolytes during long workouts or excessive sweating
• Limit excessive caffeine and alcohol intake
• Eat water-rich foods such as watermelon, cucumber, oranges, and berries
• Train during cooler parts of the day where possible

Staying Active Safely:

Movement remains important during warmer weather, but recovery becomes even more important too. Listen to your body, reduce intensity if needed, and prioritise hydration and rest.

If you’re struggling with muscle tightness, joint pain, cramps, or recovery during the heatwave, our team at FYB can help with hands-on treatment, rehabilitation, sports massage, and movement advice tailored to you.

Stay safe, stay moving, and stay hydrated this summer ☀️

See you in the clinic,

Jane x

Chartered Physiotherapist & Team Free Your Body Therapy