Backward lunge & twist
Tips from Peter:
Hold a weight (start with a 5kg exercise ball or try a heavy object if training at home such as a rucksack with books inside) fixed to your breastbone
Perform a backward lunge but keep your weight over the front leg
Try to keep your legs in a straight line as you twist, bringing your opposite elbow close to the front knee
Try to keep you back work so all of the work comes from your legs and glutes which you should feel working had before too long.
To start off, try 10 reps on each leg, 3 sets in total and allow a 1-minute recovery between sets.