Pounding the pavement, treadmill or countryside is a sure-fire way to get one’s heartbeat racing. But is it a great way to shape up or a pathway to trouble?
+ Heart disease and weight control Dr Peter Schnohr, chief cardiologist of The Copenhagen City Heart Study, says the strenuous activity of jogging offers greater heart benefits than walking: “It increases oxygen uptake to improve cardiac function, lowers blood pressure and increases insulin sensitivity.” His team calculated that joggers live five to seven years longer than non-joggers. Jogging also helps shed those kilos.
+ Osteoporosis Jogging increases loading on the femur, boosting femoral bone mass density (BMD). And you don’t need to run daily to see results. “Among our study’s joggers, 47% ran eight or fewer times a month yet still had higher BMD than non-joggers,” says researcher Michael Mussolino from the US Centres for Disease Control and Prevention.
+ Wellbeing A study at Oregon Health Sciences University found almost all joggers experience mental and emotional benefits from their exercise.
+ Brain power German neuroscientists from the University of Ulm found that 30-minute jogging sessions three times a week significantly improved concentration and visual memory. “The runners who had taken the six-week jogging course made fewer mistakes and could complete the tests much more precisely,” says researcher Ralf Reinhardt. It’s thought intense exercise manufactures new hippocampus cells and protects existing ones.
– Osteoarthritis Running loads the lower joints with more than four times the body’s weight. However, MRIs show that running causes less joint-cartilage damage than once thought.
“Most likely, running has no influence on joint damage, but people with existing deformities, previous joint damage, obesity and malalignment need to be careful,” says Dr Erik Hohmann, director of the musculoskeletal research unit at Central Queensland University. “Running increases impact loading and, in these cases, will speed up osteoarthritis,” he says.
– Breast sag A UK study found that for every mile (1.6km) a woman runs, her breasts bounced 135m, leading to irreversible breast sag. Sports bras reduce bounce by 78%.
– Skin cancer A study at the Medical University of Graz in Austria found 210 distance runners had more solar lentigines and lesions suggestive of basal cell and squamous cell carcinomas compared to non-runners. Sun exposure was not the only factor. “There is good evidence that high-intensity training such as running can lead to suppressed immune function,” says researcher Dr Christina Ambros-Rudolph. Trauma sustained during extreme exercise stimulates cytokines, proteins that can suppress cell immunity and leave athletes susceptible to infection.
Kilometre for kilometre, jogging generally burns about 25% more kilojoules than walking. However, jogging exerts extreme force on the lower joints, so walking may be a better option for overweight people or those with hip, knee or foot complaints.
People with underlying heart conditions should also steer clear of this activity. A recent Medical Journal of Australia report notes the incidence of sudden death from heart failure is seven times higher in men during jogging than during more moderate activities. That said, cardiovascular events from jogging are still rare and are usually associated with pre-existing problems.
It’s another reason to get yourself thoroughly checked out before and during any rigorous fitness plan.