It is now recognised that long periods of inactivity, combined with the cramped conditions and dehydration which can occur on long flights, can cause a number of circulatory problems, ranging from swollen ankles and tired aching legs to more serious medical conditions such as deep vein thrombosis (DVT).

Factors which contribute to the discomfort and risk associated with flying include:

• Cramped conditions that many passengers occupy during long-haul flights with restricted seating space
• Limited exercise opportunity / lack of leg movement
• Low humidity
• Reduced cabin pressure
• Dehydration