Older cyclists have been warned to avoid tight compression sports clothing because it can cause them to overheat and increase stress on the heart.
Athletes choose Lycra-style clothing to exercise because it is meant to regulate temperature, keep muscles warm to avoid strain, improve circulation, prevent 'tissue jiggle' and speed up recovery time.
However, a study by the University of Navarra in Spain found that such clothing offers no temperature-controlling benefits, and in older people can in fact increase heart rate.
"Recreational cyclists should be made aware of the possible adverse effects of this type of clothing," said Iker Leoz, a doctoral student.
The ability to regulate body temperature declines with age, which is why people over 60 are the most vulnerable population during heat waves and cold spells.
The study tested four groups of 12 people of different ages, at different temperatures to see if compression clothing helped performance and recovery.
The results showed that when exercising at 68F (20C) young people gained no benefit from tight clothing.
In the case of trained cyclists with an average age of 66, garments actually increased body temperature and in some cases increased heart rate after an intense effort.
Mr Leoz said that older people should not use heat-dissipating compression clothing, because it could increase the onset of hyperthermia - the raising of body temperature above the normal levels.
When all of the study participants were asked to run on a treadmill to the point of exhaustion, the clothing lowered performance of all participants.
Although the new research only looked at tops, previous studies have shown that compression socks can benefit runners and help speed up recovery.