Surviving Summer with POTS: A Practical Guide to Managing Heat Intolerance

Why Heat Makes POTS Worse

For people living with Postural Orthostatic Tachycardia Syndrome (POTS), summer can feel like an endurance event before they've even left the house. POTS is a form of dysautonomia in which standing triggers an excessive rise in heart rate, palpitations, dizziness, fatigue, and exercise intolerance without a drop in blood pressure (American College of Cardiology, 2026). The autonomic nervous system fails to appropriately constrict blood vessels on standing, so blood pools in the legs and the heart races to compensate (Sheldon et al., 2015).

Heat is one of the classic triggers that worsens symptoms (Sheldon et al., 2015). Other common triggers include dehydration, prolonged standing, alcohol, and rich meals (American College of Cardiology, 2026; Sheldon et al., 2015). Warm environments cause peripheral vasodilation, which compounds the already-impaired vasoconstriction response, further reducing return blood flow and magnifying the tachycardia (Sheldon et al., 2015).

The Foundation: Fluids, Salt, and Cooling

1. Optimise hydration and sodium intake

Adequate hydration and increased sodium intake (when not contraindicated) form the foundation of POTS management, because expanding circulating volume helps the body tolerate upright posture (American College of Cardiology, 2026). Sodium supplementation has been shown to improve orthostatic cerebral and peripheral vascular control in patients with orthostatic intolerance, including POTS (El-Sayed et al., 2021; Raj, 2013). This becomes even more important in summer when sweating and vasodilation increase fluid losses.

Practical tips:

• Aim for consistent fluid intake across the day rather than bolus loading

• Include salty snacks and electrolyte drinks (especially during exertion in the heat)

2. Try cold water boluses (drinking cold water)

An elegant and evidence-supported tactic: bolus drinking of cold water has been shown to blunt the heart rate rise on standing and improve vascular resistance responses in POTS patients, over and above the benefit of water drinking alone (El-Sayed et al., 2021).

3. Use cooling strategies

Standard non-pharmacological advice for orthostatic intolerance includes avoiding hot environments, hot baths, and heat exposure (Sheldon et al., 2015). In practical terms:

• Time outdoor activities for the cooler parts of the day (early morning or evening)

• Use air conditioning, fans, and cooling towels

• Wear lightweight, loose clothing

• Keep showers lukewarm rather than hot

• Consider a cooling vest if you work or exercise in the heat

4. Compression garments

Graduated compression stockings (or abdominal binders) help reduce peripheral blood pooling and can improve orthostatic tolerance (Raj, 2013). These are particularly useful on warmer days when you must be upright.

5. Postural hygiene

Slow, careful positional changes; dorsiflexing the feet before standing; and avoiding prolonged standing or working with arms raised above shoulder height all reduce symptom triggers.

Exercise: Don't Skip It, Adapt It

Exercise remains a cornerstone of POTS management, but it must be structured and progressive. Structured programs commonly begin with recumbent exercise modalities such as cycling, rowing, or swimming before advancing toward upright activity (American College of Cardiology, 2026). Progressive strength training, particularly targeting the core and lower-extremity muscles, improves orthostatic tolerance and functional capacity (American College of Cardiology, 2026).

Summer-specific exercise adaptations

• Exercise indoors with air conditioning during the hottest parts of the day

• If you have access to a pool this is a great alternative in summer

• Pre-cool before exertion: cool shower, cold-water drinking, and cooling towels before exercise

• Pre-hydrate with sodium-containing fluids and bring electrolyte drinks for sessions longer than 30 minutes

• Wear compression garments during and after exercise to support venous return if possible

• Pace it: shorter, more frequent sessions are often better tolerated than one long session

• Avoid vigorous exercise in direct heat.

Heat intolerance in POTS is real, but manageable. With a combination of volume expansion (fluids + salt), cooling strategies, compression, and carefully paced exercise, patients can enjoy summer without their symptoms dictating the day (American College of Cardiology, 2026; Raj, 2013). Team up with your GP, cardiologist, and allied health team to tailor these strategies to your individual needs.

Disclaimer: This blog is for educational purposes only and does not replace personalised medical advice. Always consult your treating clinician before changing your management plan.