Sexual activity puts extra demands on the heart and lungs, the BLF says
People with breathing problems have been offered some timely Valentine's Day advice to help them enjoy a fulfilling love life.
The British Lung Foundation says sufferers may worry during sex that they "will become too short of breath or may need to cough up phlegm".
The BLF's Dr Noemi Eiser said: "Living with a lung condition doesn't mean you have to compromise on intimacy."
Its leaflet Sex and Breathlessness has advice and tips on sexual positions.
"Have sex when you feel rested and your breathing is at its best"
"Try coughing up phlegm before sex or avoid having sex in the morning when it's likely you will be producing more phlegm"
"Avoid sex after a heavy meal or alcohol. Your breathing may be more difficult if you have a full stomach and feel bloated"
"If you become very short of breath during intercourse, try pausing to take a few slow, deep breaths from your diaphragm rather than stopping altogether"
"Don't forget that all intimacy should be for fun and your enjoyment. Laugh and talk over any difficulties."
Source: British Lung Foundation
In a press release, the BLF said sexual activity required energy and put demands on the heart and lungs.
This results in extra breathing and raised blood pressure, it adds.
It continues: "This is the same for everyone, but for those living with lung conditions it can stop them from enjoying the experience.
"Enjoying a fulfilling sex life should not be comprised if people are living with a lung condition."
Dr Noemi Eiser, the BLF's medical director, said communication was vital in overcoming such diseases.
She added: "It is important that you talk to your partner about any worries and are open-minded and understanding.
"Creating a comfortable and trusting environment will prevent stress and shortness of breath."