February 2024: A famous London Bus Study by Morris and colleagues in 1949 found sedentary drivers of London’s double-decker buses had higher rates of cardiovascular disease than conductors who moved around the bus checking passenger’s tickets.
Curtin University Associate Professor Joanne McVeigh, an international expert in the measurement of physical activity and sedentary behaviour, explains the bus study—which was radical at the time—provided the first evidence of the poor health outcomes from too little activity and too much sitting.
We know now prolonged bouts of sitting are particularly poor for our health. A 2019 study reported physical inactivity in Australia costs a staggering $15.6 billion each year due to healthcare costs and lost . “And the burden is two-fold,” says A/Prof McVeigh. “Too many people sit for too long and too many people are insufficiently active.”
For thirty-odd years, Raine study researchers have collected data on participants physical activity and hours spent in front of screens, using questionnaires, pedometers to count people’s steps and other wearable devices to collect detailed information.
Raine study participants answer the same questions year after year, so we can see how patterns of behaviour might be associated with certain health outcomes, she says. Her team were able to show how a group of Gen 2 participants that watched less TV during childhood and adolescence, had lower body fat percentage and greater bone mass at age 20 and 22, compared to other groups, and better self-reported physical health.
They learned any movement counts, that participants are most active on Thursdays and least active on Sundays. This sort of information makes it easier to tailor health promotion and target sedentary behaviours.
For the generations follow-up study, participants wear a 24/7 waterproof device attached to their thigh so A/Prof McVeigh and her team can tease out more associated health outcomes from sitting and standing.
Her team is also exploring the association of physical activity with body composition, mental health, myopia, bone mass, epigenetic age acceleration, fitness, artery function and retinal nerve fibre thickness.
Few researchers have access to such a rich historical database. These studies are the largest and longest trajectories of physical behaviours in the world, so the Raine Study is attracting a lot of attention from international cohorts, she says.
“Study outcomes can actually influence policy or guidelines,” A/Prof McVeigh says. For example, the World Health Organisation recently updated their guidelines on physical activity and sedentary behaviour based on data derived from Raine study.
“It’s amazing to think that our study here in Perth is impacting global guidelines,” she says. “I hope in 50 years people will be talking about the amazing Raine Study findings and the behavioural changes we encouraged to improve health outcomes.”
Watch her oral presentation here, or read the Research Papers below:
Relationship between TV Watching during Childhood and Adolescence, and Artery Function in Adulthood