During every dive, our bodies absorb nitrogen from the compressed gas we breathe. The deeper and longer the dive, the more nitrogen we take on. By ascending slowly and performing safety stops, we allow that gas to start off-gassing while we’re still underwater. If you ascend too quickly or skip safety stops, nitrogen can form bubbles in the bloodstream, causing decompression sickness (DCS).
What many divers don’t realise is that off-gassing continues for several hours after the dive. During this time, there are several things you should avoid to help your body release nitrogen safely.
Flying or Heading to High Altitudes
You’ve probably heard this rule during your dive training – don’t fly after diving. When you ascend to altitude, whether in an aircraft or driving up a mountain, the air pressure drops. This can cause remaining nitrogen to expand too quickly, just like ascending too fast underwater.
- Wait at least 12 hours after a single dive
- Wait 18 hours after multiple dives
- Wait 24 hours if you exceeded no-decompression limits or missed a safety stop
The same logic applies to mountain trips. Avoid climbing or driving higher than 1,000 ft (300 m) for 24 hours after diving. Plan your travel itinerary with this in mind – no diving on your last day, and no mountain excursions after a dive.
Trip tip: Schedule your dives early in the trip and save flights or scenic mountain drives for the end.
Freediving or Breath-Hold Diving
Freediving is an incredible way to e
njoy the ocean, but not right after a scuba dive. There is still nitrogen in your body from the dive. Going back to depth and ascending quickly can disrupt off-gassing and increase DCS risk.
- Wait 12 hours after one dive
- Wait 18 hours after multiple dives
When in doubt, stay on the surface and enjoy snorkelling instead.
Hot Baths, Showers, or Hot Tubs
After a cold dive, a hot shower sounds appealing, but it’s best to wait. Hot water warms tissues rapidly, which can affect how nitrogen behaves in the body and may encourage bubble formation.
Divers Alert Network recommends waiting 5 to 30 minutes after a dive before hot-water immersion. If you can’t wait, choose a lukewarm shower and dive conservatively.
Deep-Tissue Massage
Massages are a great way to relax on holiday, just not immediately after diving. Increased circulation may mobilise bubbles, and muscle soreness from deep massage can m
ask or mimic symptoms of decompression sickness.
Exercising after Diving
Another important rule for scuba divers is to avoid physical exercise after diving. Physical exertion following scuba diving—particularly the kind that involves heavy use of muscles, joints, or rapid limb movement—could increase the formation of bubbles in the body, which can increase the risk of decompression sickness. Examples of exercise include:
- Hitting the gym for weight training
- Swimming or running after scuba diving
- Playing sports, like beach volleyball or soccer
- Even vigorous dancing!
According to the Divers Alert Network (DAN), the consensus among researchers is to wait at least 4-6 hours before exercising after scuba diving. Previously, this guidance was 24 hours, but that is now considered impractical. Of course (as with many other activities on this list), the longer the interval you leave between diving and exercising, the less risk there will be of decompression sickness.
Recognising the Signs of Decompression Sickness
- Joint or muscle pain
- Tingling, numbness, or pins and needles
- Fatigue or weakness
- Skin rash or itching
- Dizziness, confusion, or headache
- Impaired vision or hearing
- Nausea, vomiting, coughing up blood
- Shivering or loss of consciousness
If you notice any of these symptoms, stop diving and seek medical help immediately. Breathe 100% oxygen if available and contact emergency services or DAN.
