How does smoking affect your lungs?

Smoking has both immediate and long-term effects on several physiological systems used in intense exercise. Intense or maximal exercise requires these systems to be stretched to their full capacity.

Any reduction in this peak capacity will result in reduced performance. Furthermore, there is a temporary drop in immune function following intense exercise, which leaves an ‘open window’ for infection. There’s also increasing recognition that the immune system plays an important role in recognising and killing early cancer cells; therefore the combination of smoking and intense exercise can’t be a good one.

The effects of smoking on the respiratory system are most obvious. After one cigarette, the cilia (hairs that waft phlegm and other pollutants out of the lungs) are suppressed. With long-term smoking, the cilia are removed completely, and smokers have to cough to get pollutants out of the lungs. The risk of infection is greatly increased. Smokers have more frequent infections, and this will get in the way of training. More serious infections such as pneumonia can cause lung destruction on a permanent basis. With smoking, the air sacs (alveoli) in the lungs are progressively destroyed, and smoking eventually leads to reduced lung capacity.

This will lead to reduced respiratory function at all levels of exercise, but will be particularly noticeable with higher-intensity exercise because the higher intensity simply won’t be there.

Immediately after a cigarette the blood vessels tighten (vasoconstriction), leading to reduced oxygen delivery to the working muscles. The heart has to work harder to achieve the same performance, meaning blood pressure rises to meet demand. Normally blood pressure does need to rise during intense exercise in order to improve the perfusion pressure to muscles; but in the context of smoking, the heart is working unnecessarily hard.

• Circulatory system: what it is and how exercise affects it
• Why athletes should get their hearts checked

In the long-term, smoking can lead to atherosclerosis, a hardening and blockage of the arteries throughout the whole body. The coronary arteries that supply the heart progressively narrow, meaning the heart cannot perfuse itself properly; this leads to a poor cardiac output. Smokers develop angina, heart attacks and heart (pump) failure.

Overall, smoking is associated with innumerable harms for a triathlete, many of which come from smoking only one cigarette.

Dr Creaney is a Consultant in Sport & Exercise Medicine with interests in musculoskeletal medicine, sports injuries and exercise medicine. He is also a team doctor with British Athletics

Dr Leon Creaney Consultant physician in musculoskeletal, sport & exercise medicine

About

Dr Leon Creaney is a consultant physician in sport and exercise medicine. He sees private patients with musculoskeletal, orthopaedic and sports medicine problems, and medical symptoms during exercise. Dr Creaney (BMedSci MB ChB MRCP FFSEM) trained in London at several prestigious centres including the Olympic Medical Institute, DMRC Headley Court (Army Rehabilitation Centre), The Royal National Orthopaedic Hospital and the Royal London Hospital. He qualified as a consultant in 2009, eight years after leaving the University of Sheffield. Since then he has worked as an NHS Consultant in Sheffield, the Department of Health (DH), and Aldershot Garrision RRU. He’s also worked for British Athletics and Liverpool FC women as a team doctor. He now works exclusively in private practice in Manchester, Wilmslow and Warrington. Dr Creaney treats all orthopaedic complaints from head-to-toe. As a physician, Dr Creaney uses a combination of physical therapy, injections and medicines to treat pain and injury, and works closely with leading surgeons to prepare those patients who need an operation.