The midlife guide to interval training: how to get fit in 23 minutes... without hurting yourself

Interval training replaces the bog standard exercise session with alternating bursts of high and low intensity effort. It’s a simple idea that can have dramatic effects on our fitness.

One of those effects has been revealed this week by the British Journal of Sports Medicine. The journal’s findings, which draw on 36 studies involving approximately 1,000 people, show that a burst of intense exercise for 23 minutes can burn more fat than much longer, traditional gym routines.

The most eyebrow-raising results in the survey have to do with the participants who did “sprint training”, which is used in running and cycling and involves going like the clappers for 30 seconds before slowing down for four minutes of low-intensity exertion. Participants doing that lost 6pc of body fat, compared to 3.4pc lost by those doing a standard 41 minute stint in the gym.

The findings are likely to boost the popularity of High Intensity Interval Training (HIIT) still further - as if its supposed ability to mitigate the ageing process of muscles weren’t already enough. In fact, for time-poor midlifers with one eye on their expanding midriffs, it might look like a magic bullet. But is there a danger that HIIT might actually be a kind of Get Fit Quick scheme, unsuitable for anyone who isn’t a musclebound 20something in premium activewear? Could it be dangerous?

Experts from Hampshire’s School of Sport, Health and Social Sciences have acknowledged that HIIT "might increase the risk of injury and impose higher cardiovascular stress". The problem, often, is felt among those who don't already have a lot of exercise under their belt.

Annie Deadman is a trainer and author of The 21-Day Blast Plan who specialises in helping people in their forties and fifties get fit. She warns against pushing too hard too soon to reach for those attention-grabbing stats. “If someone came to me who was new to fitness, and they were healthy, with no injuries, and they wanted a HIIT session, then I would proceed with great caution,” she says. “Going straight into a high impact HIIT work isn’t a good idea for an untrained midlifer.”

The crucial word there is 'impact'. Deadman is adamant that high intensity needn’t mean high impact, and emphasises low impact work that doesn’t place a strain on joints. “Say you’re doing star jumps”, she explains. “Somebody who is untrained would find that very difficult because it demands a lot of puff, and it’s hard on their knees. So they would do a lower impact version of that.”

If your image of a HIIT class is of people going hammer and tongs on the high knee jumps, this is where you can breathe a sigh of relief. It’s possible to do low impact versions of high impact cardio exercises and still enjoy the benefits of interval training described in the new study. Simply stepping it out while the person next to you does the high knees, for example, is still interval training, it just avoids the strain on the joints that can come with high impact work.

Strength work like squats and leg press is crucial, and needn’t require a gym. This will strengthen around the joints, paving the way if you want to progress from low to high impact work.

The interval approach can also be incorporated into exercises we are already doing, rather than having to go to a specialised gym class. “I see people swimming up and down, and barely raising their heart rate”, Deadman confirms. “They could make that harder for themselves and get fitter by doing swimming slowly for two lengths, and then faster for one length, that kind of thing. That’s a high interval training effect.”

The same goes for running: rather than putting yourself through the pain of running long distances, you can take a more tailored approach. “You just need to, say, run 10 paces, walk 10 paces”, she suggests.

Depending on your fitness goals, Deadman also suggests supplementing your workouts with an eating plan geared towards wellness. Diet, she says, is a word she hates, but she does recommend certain approaches. “You feel well because you’re giving up foods which fight in the digestive system a little bit”, she says, citing cutting down on wheat, eating good forms of glycemic carbohydrate, enough vegetables for vitamins and minerals and plenty of protein to feed muscles.

She also advocates cutting down on alcohol and caffeine, though concedes this isn’t exactly “a bunch of laughs”. Still, all those endorphins should more than make up for it.

Crucially, there is no one-size-fits-all approach when it comes to interval training. Intensity is subjective based on your fitness level, and it’s important to not push harder than you should. Despite a great amount of bluster about ‘all pain no gain’ in the gym world, a HIIT class should leave you feeling invigorated, not totally exhausted.

Annie Deadman's Low Impact Interval Workout

The following workout should take 23 minutes or a little less minutes and is all is all low impact.  The first two sections have two resistance exercises and one higher intensity exercise.

Warm up

• 5 squats and 10 tap side-to-side, x 3

• 10 crunches, 10 mountain climbers (all on the floor), x 3

• 10 standing kicks, 10 half star jumps, x 3 with a rest in between.

Lower Body

• Slow squats, 40 seconds

• Glute bridge (lie on your back, knees bent, feet flat on the floor, and lift hips up and down), 30 seconds

• Toe taps (in a standing position, almost running on the spot, but not lifting feet very high), 15/20/25 seconds (which means 15 seconds first round, then 20 secs second round, then 25 seconds, with short rests in between).

Rest 20-40 seconds  Repeat x 3.  

Upper Body and Core

• Box press-ups, 30 seconds

• Oblique crunches (on your back, feet flat on floor, knees bent, hands behind head, reach out with back of the hand to the opposite knee, then repeat other side), 40 seconds

• Double side step (take a step to one side and into a squat. Repeat, then go back the other way.  The deeper you, the harder it is). 15/20/25 seconds, as per section 1.

Rest 20-40 seconds.  Repeat x 3

Low impact resistance and cardio work

• Half star jumps

• Sumo squats (squats but with feet turned out a little to hit the glutes more – do them nice and slowly)

• Walking ladder climb (high knees with arms up too, only walking pace, but quite vigorous).

Do each exercise in Section 3 for 15 seconds, with minimum rest in between. Rest for 20 seconds once all three are complete, then repeat the list for 20 seconds each. Rest another 20 seconds, then repeat again, this time for 30 seconds.

Rest. Do a little dance and feel super smug.