If you have 10 minutes…

High intensity interval training (HIIT) gets you fit fast. Intensive bursts of exercise are followed by short intervals working at a lower intensity. Benefits include an increase in hormones (including human growth hormone), and enzymes that increase metabolic rate, an increase in activity of heart and respiratory muscles and a decrease in subcutaneous fat. It’s what most animals in the wild do and is the perfect method to increase fitness levels for anyone who’s pressed for time.

If you have 45 minutes…

A lunchtime workout will reduce stress levels, increase energy and help you be more productive for the rest of the day. There are lots of new Total Body classes springing up all over the UK – and at Grace, we’re pioneering these new, highly practical classes, which include Target Spin, with a personalised heart-rate monitor to get you working at optimal level, and Get Set Go, a HIIT class created by Jenni Rivett, designed with the female body in mind.

Try two speedy toning exercises:

• Ice-skater lunges. Start feet shoulder-width apart. Step forward and to the side, so your lead foot is in front of your back foot (like a curtsy). Lower your body until your front knee is bent 90 degrees. Pause, then return to the starting position and repeat with your other leg.
• Grasshopper. In a push-up position, bend your left knee; slide your leg underneath your body. Return left leg to the starting position, then repeat with your right leg.

For more information about fitness at Grace Belgravia, visit gracebelgravia.com/gym/duncans-workout-tips

Photograph: iStock