Photo: Cruise Gym from alantankenghoe's Flickr photo stream

The last time I met a colleague, let’s call her M, she was sporting a limp and a walking stick. Her evidently painful injury had been sustained as a result of health-promoting exercise. Troubled by her injury M, with the authority of a scholar of public health, asked ‘What is an appropriate dose of exercise?’ It was a question I felt unable to answer.

While engaged in my morning micro-run, I realised that the answer was obvious: ‘Less than you’re doing right now, my friend!’ Given that M is an evidence-based girl, this answer probably would not suffice. So I am pleased to offer her a proper research paper to persuade her to run (and so perhaps hurt), less. Mads Rosenkilde and colleagues of the University of Copenhagen have published the results of a randomized controlled trial that recruited 61 sedentary and overweight men.

The men were divided into 3 groups: intense exercise (60 minutes 3 times per week), moderate exercise (30 minutes 3 times per week), or no change to their sedentary lifestyle. Not surprisingly nothing changed for the men who remained sedentary. The surprise result was that men doing moderate exercise lost more weight than those doing intense exercise.

M is neither a man, nor overweight, but perhaps the message that moderate exercise can be more beneficial than intense exercise could appeal nonetheless to a slim woman with a sore leg.