Muscles worked
This is an ordinary squat with added weight, so the work falls mainly on your quads and glutes, with your inner thighs helping. Your back and trunk keep your upper body steady under the load. Because the rucksack sits behind you, your centre of gravity moves back and you lean a little further forward than without a bag. Turn the rucksack round and wear it on your chest, and the exercise becomes more like a goblet squat: your torso stays more upright and your quads take a slightly bigger share.
Common mistakes
- The rucksack is loosely packed. Shifting contents tug at you on every rep. Pack it tightly, put the heaviest things nearest your back and fill the gaps with a towel or clothes.
- Your depth shrinks as the weight goes up. Many people squat higher with the bag on. Touch a chair or stool behind you lightly with your bum on every rep, so the depth stays the same.
- Your toes point straight ahead. For many people the hips run out of room before they get deep when the feet are dead straight. Turn your toes out a little and let your knees follow them.
Variations and alternatives
- The bodyweight squat without the bag, to learn the movement before you add weight.
- The goblet squat with a dumbbell held at your chest is the gym equivalent and easy to load up.
- The backpack lunge with the same bag, once it has become too light for squatting on two legs.
Sets and reps
A rucksack only holds a limited amount of weight, so sets tend to be longer: 3 sets of 12 to 20 reps is a good target. Stop with a couple of reps in reserve in the early sets and go closer to your limit in the last one. In the guide to sets and reps you can see how your goal sets the number of reps.
Stand on a bathroom scale with and without the rucksack. The difference is the weight you are lifting, and you can log it just like a barbell. Then add one book or water bottle at a time. Once the bag is full, lower more slowly or pause at the bottom. That turns the rucksack into a tool for progressive overload.