If you don't know who Tracy Anderson is then you really should read more gossip magazines. Anderson is the personal trainer to celebrities like Gwyneth Paltrow and Kim Kardashian and her training program called 'The Method' is credited with helping them look - well, like Gwyneth Paltrow and Kim Kardashian. For those of us who can't afford one to one sessions with Anderson or aren't around the corner from her studios in New York, Los Angeles or The Hamptons, there are DVDs to show us the way.
I'm all for anything that gets people moving - and Anderson's dance-like movements certainly do that - but I'm stumped by one of her core rules of training: that women shouldn't train with weights of more than three pounds (about 1.3 kilos).
I don't know where this idea comes from - not from any strength training manual that I'm familiar with. I also don't know how big Anderson's own babies were but I do know that most women give birth to babies that weigh more than one and a bit kilos. These newborns also have a habit of gaining weight so that by the time they turn into toddlers their mothers may be hefting ten kilos on one hip with another five kilos of groceries on the other shoulder.
Anderson's website, which has three pound dumbbells for sale - but only in pink- explains that her program gets women in shape by focussing on the body's smaller muscles rather than the larger muscles.
"Most gym programs overwork major muscle groups," Anderson once said in an interview with the New York Times. "Repetition builds and bulks muscles."
For women who don't normally exercise, this approach would help them lose weight, as long as they changed their diet too, points out Michelle Drielsma, a strength coach and exercise physiologist based on Sydney's Northern Beaches.
"Using small weights with lots of repetitions, as Anderson does, helps to strengthen muscles a bit - but you won't progress very far if you stay on three pound weights," she says.
"There's also the argument that working out with heavier weights will support a graceful ageing process - studies have repeatedly shown that through moderate to heavy strength training we develop stronger bones, tendons, ligaments and healthy muscle," she points out. "Being able to move and lift well helps you maintain good function as you age, but I don't think Anderson's workouts help to improve the ability to move through life more easily as you get older.
"Compared to heavier weights, very light weights also do very little to promote better bone strength - to do that you need to put more of a load on to ligaments and joints to stimulate the bone."
As for that tired old cliché about women becoming bulky by training with heavier weights, that doesn't hold true either. Men have around 10 to 20 times more testosterone than women, according to Drielsma and this influences muscle size. Genes also play a role in how much muscle women gain too - but in general most women don't bulk up.
"It's also usually the fat around the muscle that gives the appearance of bulk, rather than the muscle itself," she says.
Anderson's program also requires an hour a day six days a week, but Drielsma believes that exercising for less time, but using heavier weights gives women better results in terms of weight loss and shape.
"Using heavier weights to train the larger muscles of the lower body with exercises like squats and lunges not only improves your body's function, it also increases muscle mass and this helps you to burn more fat.
"But it's also good to mix your exercise routine up. You can do something like Tracy Anderson's program - but it's good to use some heavier weights too."