Research
Adherence
Smoking is associated with lower cardiorespiratory fitness and respiratory function, and smoking cessation is associated with better maintenance of these functions over time.
Quitting smoking improves cardiorespiratory fitness over time, even if you were a smoker previously. Never smoking is associated with the best maintenance of fitness.
GoodSupportsHIGH confidence
Smoking was related to lower cardiorespiratory fitness and respiratory function. ... After controlling for other variables, adults who never smoked had a greater mean change in MTT (1.50 minutes) than quitters (0.81 minute)... and persistent smokers (0.58 minute).
Why this rating
Large longitudinal cohort with controlled covariates.
Source
Effects of physical activity on exercise tests and respiratory function
Yiling J. Cheng et al. · British Journal of Sports Medicine · 2003
DOI 10.1136/bjsm.37.6.521
cohort · n=24536Cited 219×
Read the paper DOI resolved against Crossref · corpus check 2026-06-10
Related findings · Adherence
- Regular physical activity (at least 150 minutes/week of moderate-intensity) reduces all-cause and cardiovascular mortality by 20-30% and lowers the risk of type 2 diabetes by 25-35%.Strong
- Increasing physical activity from a sedentary lifestyle to an active one in middle adulthood significantly reduces the risk of coronary events compared to remaining sedentary.Strong
- Resistance exercise is the only intervention capable of consistently restoring muscle function and strength in sarcopenia, partially overcoming age-related anabolic resistance.Strong
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