20/06/2026
When should you increase sodium?
Most runners and cyclists know they need to drink during longer sessions. The harder bit is knowing when lower-strength hydration may not be enough.
A few signs it might be worth thinking about more sodium:
• Hot or humid conditions
• Long sessions of 2–3+ hours
• Heavy sweat rate
• White salt marks on kit
• Cramp, headaches or feeling rough later
• Drinking plenty but still feeling flat
For some people, 500–600mg of sodium per litre may be enough.
For heavier or saltier sweaters, especially in heat or longer events, moving towards 1000mg or 1500mg per litre can be worth testing. Not everyone needs the strongest mix all day.
But if you know you sweat heavily, don’t leave sodium as an afterthought.
Test it in training. Learn what works. Do you feel stronger toward the end of the session than you would typically? Don’t guess on race day.
Short and easy: keep it simple.
Long, hot or sweaty: think fluid + sodium.