Here’s how you can give it a go:

1

WALKING

Start by adding intervals of power walking – as fast as you can walk – or jogging for up to 30 seconds. Do this at least six times during a 30-minute walk. Then, when you get comfortable with interval training, intensify your workout so you’re doing 10-12 speedy intervals over 30 minutes, about one interval every 2.5-3 minutes. You can time these fast intervals using the stopwatch on your mobile phone, or the second hand on your watch.

2

SWIMMING

Combine 10-20 laps of swimming with other water exercises:

Kicking only Using a kickboard for balance, add a lap of fast kicking then swim 3-5 laps of regular swimming.

Arms only For 3-5 laps of every 10-20 laps, use your arms to propel you down the pool, while holding a buoy between your legs to keep you afloat.

Sprints Add a half- or a full-lap sprint of a stroke, for 3-5 laps of every 10-20 laps that you swim.

Alternate strokes Add a sprint lap of one stroke, and then perform 3-5 laps of another stroke.

3

CYCLING

TRY THESE:

Flat road Add in 6-8 of your fastest sprints for 30-60 seconds in a 30-minute workout.

Gentle hills Include 3-6 gentle hills that allow for a seated climb during the course of a 30-minute workout.

Big hills Add in 2-4 big hills for a standing climb in your 30-minute workout. When doing a combination of hills and flat roads, use distant landmarks, like houses, to give you something to aim towards during intervals of speed.

4

CIRCUIT TRAINING

Circuit training is basically interval training, but with resistance exercises and cardio in the same session. This means you can complete a set of weights in a chair, then do 1-2 minutes of cycling, jogging or marching on the spot. For added intensity, do a different cardio and resistance exercise at each station. Or you can add in intervals of cardio in between doing sets of resistance – such as periods of marching on the spot in between doing sets of hand weights.