The fastest 60-year-old woman in the world, Torontonian Karla Del Grande, once thought, like the vast majority of us, that running means distance running. Then, at 50, while trying to boost her speed for a half-marathon, she hit the track for interval training and rediscovered her love of speed.
She ditched the long run, took up sprinting and now considers herself fitter, stronger and more powerful than she's ever been in her life, including when she did high-school track.
Ten years later, Del Grande broke world records in the 200- and 400-metre distances, and indoors in the 60. That required besting times set by Philippa Raschker, the phenomenal American masters track athlete who, among her many accomplishments, was featured naked – at the age of 63 – in the 2010 Bodies We Want issue of ESPN The Magazine.
Del Grande, remarkably strong for her slender figure, will try to best her records at the Canadian Indoors Masters Championships March 15-16 at York University and break the outdoor 100-metre world record this summer. Yet what she really wants is for more women to discover the fun and benefits of masters track.
She gets why they don't. The retired teacher once thought that sprinting was for kids, not adults. Now, like many exercise physiologists, she's realizing that high-intensity interval training (HIT) is powerful medicine for stalling aging.
"Aging doesn't have to be about frailty, aches and pains," she told me. "That's about not training, not testing yourself. You have to say to yourself, 'Is that what I want? Do I have to accept that?' Look around and see what other women are accomplishing. I'm trying to show what 60-year-old women can do."
It's as if she has turned back the clock: She ran track at high school and university, and at 18 she ran 200 metres in 25.2 seconds; 40 years later (and after a 30-year hiatus from running), her world-record time is 28.11 seconds. Speed training, she contends, gives her a greater feeling of confidence and well being: "The body recovers and I feel 'wow.'"
That "wow" factor? Studies show that sprinting tops distance running for building bone density and, in women, muscle mass. As well, HIT-style exercise also prompts the body to secrete growth hormone (GH), often called the youth hormone; it helps maintain body weight and rejuvenates muscle and connective tissue (including collagen, a major component of skin). GH starts to diminish in our 30s, but vigorous exercise sparks it back up.
Richard Godfrey, a specialist in exercise-induced GH response at London's Brunel University, believes that exercise for older adults should focus on promoting human growth hormone release to counter the effects of aging. He recommends aerobic high-intensity efforts – say, five sets of one-minute hard effort followed by one-minute easy effort – the sort of interval training that distance runners can do (sprinting has a high risk of injury for the untrained). He says exercising for 10 minutes above "threshold" – 60 to 70 per cent of max heart rate – in any session produces the greatest sustained GH spike. If pressed for time, he ditches endurance for intensity – six reps of hard/easy for 12 minutes in total.
Studies at McMaster University suggest that 18 minutes of high-intensity interval training per week (excluding warm up and cool down) can deliver many of the health benefits as five hours of sustained moderate exercise.
As Del Grande told me, "It's in pushing yourself a little harder, rather than going along at the same speed, that you surprise yourself. You find there are depths you can reach that are satisfying."
Margaret Webb's reflections on running, Older, Faster, Stronger, will be published in October by Rodale Books.