The arrival of a baby rarely heralds a period of optimum fitness for parents. With no time or energy for trips to the gym, and grabbing snacks an easy alternative to cooking, new parents can soon find themselves out of shape and puff. And poor fathers can't even use the excuse of a recovering post-childbirth body or the extra calorific needs of a breastfeeding mother.

But one father claims to have found the solution. Turn your baby into your gym, says American naturopath, Joshua Levitt, and your body can be a temple once more. In his new book Baby Barbells he sets out a series of exercises he says will build muscle as well as the bond with your baby.

Levitt, 36, a father of three, came up with the idea when his oldest daughter, Sircia, now eight, was a baby. "I came home from a long working day and my wife just handed me the cranky baby and said it was my turn," he recalls. When cuddles and soothing words had no effect, Levitt lay down on his back with Sircia on his chest and began lifting her up and down. "I was saying, 'baby up, baby down' and Sircia started giggling away. At the same time I started to feel the burn in my triceps. I realised I was on to something. This was multi-tasking."

The baby bench press, as Levitt calls it, now forms part of a workout for new fathers and babies that includes such cutely-named exercises as tot squats, lullaby lunges and peek-a-boo pop-ups.

It may, as Levitt readily admits, be a bit of fun, but his book's message and benefits are serious, he insists. "I knew I wouldn't be winning any body-building contests this way, but I realised at that point that I was in the worst shape of my life. I had to do something." Through his work Levitt was aware that lack of physical activity was a major risk factor for a huge number of health problems.

"I was trying to be the husband and the father and the [naturopathic] doctor that I wanted to be, and exercise, which has always been a big part of my life, had simply evaporated. Here was a way to bring Sircia in and she was loving it."

Hands-on exercise sessions became part of the daily routine in the Levitt household and the habit has grown with the family. Sircia was followed by Callie, seven, and son Zaiah, four, all of whom continue to treat their father as a "human jungle gym".

He is delighted at their enthusiasm and the chance to build on their fitness together. "As they get bigger and they can balance better, they can do different stunts and I in turn get stronger and fitter. This is about making physical activity a part of daily life. It is not something that should stop when the baby starts toddling about."

While Levitt is delighted at the genuine improvement to his fitness from his routine, he is just as passionate about the benefit to his relationship with his children. "Being an involved father is very important to me. I wanted to be part of their day-to-day lives. The rewards from that for fathers, children and families are huge."

Developing the baby barbells idea gave Levitt a blueprint for a unique relationship with his children, and it is one he hopes will inspire other fathers. "Dads are so much more present now, which is great, but many do feel a bit lost about what to actually do. This is within the male comfort zone and it demands a father's full attention. You can't use a BlackBerry while you do it." 

Levitt makes no claim to having invented the idea of physical play – his own father did "circus baby tricks" – but hopes his ideas can build on the age-old tradition of rough and tumble while giving what he sees as a "high health risk" section of society some ways to become more active.

He admits that his ideas have not always led to family harmony though. "My wife does sometimes have to look the other way when we try something new, but we have no serious injuries to report so far."

Do try this at home

▶ Baby bench press (works the chest): Lie on your back holding baby under the armpits. Lift up and down.

▶ Precious cargo row (shoulders): Buckle baby into the car seat and place next to a chair. Resting one hand and knee on the chair, bend at the hips and lift and lower car seat with a straight back.

▶ Tot squats (hamstrings): Standing with feet shoulder-width apart cradle baby with both arms. Keeping a straight back repeat deep knee bends.

▶ Peek-a-boo pop-ups (lower back): Lie face down on the floor using your outstretched arms to support baby in front of you. Pop up lifting your upper and lower body (and baby's hands) and hold the position.

Baby Barbells by Joshua Levitt is published by Running Press, £7.99, on 30 June.