Ask a lot of people what they do for exercise and they will mutter something about "going for a walk". Whether they are trying to shift the kilos, increase their cardiovascular fitness or just clear their heads, enough people are trudging around the block every morning and evening to make walking the most popular exercise in the country. It's gentle, low-impact, almost everyone knows how to do it, and brisk walking can reduce the risk of heart attack as much as jogging.
But Grant Schofield, professor of public health at AUT and the director of the centre for physical activity and nutrition, says how effective walking is as an exercise depends on what you are trying to achieve with it.
"Any movement is good movement," he says. "If you're not sitting down, then it's good on some level."
For a lot of people, walking is the perfect way to start improving fitness. Schofield says a walking programme is never going to prepare you to run a half marathon, but it is a really good way to ease from being a couch potato into being a regular exerciser.
If you have been sedentary for a while, going straight into running is not generally a good idea because it is too intense. Exercisers should aim to get to about 60 per cent or 70 per cent of their maximum heart rate to build their endurance and burn fat - and for a lot of people, walking is enough to get them into that zone.
Energy expenditure is measured in mets - one met is what is required by the body when you are lying down. The minimum required for an exercise to be classified as "moderate activity" is three mets, which you can achieve through brisk walking. This kind of activity has lots of benefits such as burning energy and improving cardiovascular health, but if you really want to get fit, you need to ramp up to about five mets. That would mean including some steps or hills in your walk.
If you are starting out on a walking programme, aim for half an hour every second day, and build up to going for a walk daily. Get some good walking shoes - even shoes that are six months old may have worn out their cushioning. Take a friend with you to keep you motivated and to measure your exertion level. You should be able to keep up a conversation as you walk.
Nordic poles are popular with some walkers as a way to turn walking into a full-body exercise. The poles are moved in time with the walker's steps, a bit like cross-country skiing. But Schofield says he is a bit undecided about their benefits. He says they could be seen to turn what is the most basic of exercises into something a bit inaccessible. "They increase energy expenditure but they are weird. They marginalise what is an everyday activity." But he says they are good for anyone who is a bit unsteady on their feet.
Schofield says people could be accumulating more walking during the day than they realise, especially if they are naturally fidgety and find it hard to sit still. "Some people accumulate 5km during the day. They get up, walk to the printer, to get a cup of coffee ... some people are stationary and some people move around."
He says that kind of incidental activity is really helpful and has fitness benefits. "People who don't get up and move around tend to be less fit." Take every opportunity you can to walk during the day - get off the bus earlier in the morning, walk to talk to colleagues instead of emailing and always take the stairs instead of the lift. Accumulating exercise is as good as getting it all in one hit. A pedometer can help keep track of how many steps you have taken. Aim for 10,000 a day.
If you really want to stick to a walking routine, get a dog to take with you. Schofield says he has done research that showed dog owners were fitter, healthier and walked more than non-dog owners. "Walking is good for dog health and behaviour as well as good for human health and behaviour."