The Bent Knee Back To Side Kick is a beginner-level squat movement that trains the hamstrings using bodyweight. Because the primary movers contribute to the movement, the payoff shows up in overall performance in this pattern. What separates this variation from other hamstrings work is that it is emphasising a lateral movement path — a detail that changes which fibres take the load and how much stability the movement demands. The 'Bent Knee Back Side' designation is not cosmetic — it tells you the specific setup and line of pull that separates this from its close relatives. Support comes from the glutes, hamstrings, and calves; the glutes in particular help extend and externally rotate the hip, which is why fatigue there often shows up before the hamstrings is fully worked. Training this with bodyweight needs no equipment at all and can be done virtually anywhere, though it is harder to load progressively once you outgrow it. Most lifters place the Bent Knee Back To Side Kick in the early portion of a hamstrings session. The pattern is accessible enough to learn in a single session, which makes it a sound entry point before progressing to heavier or more complex variations.
Muscles Worked
The Bent Knee Back To Side Kick is primarily a legs exercise, but it is never only the legs doing the work.
Legs
75%
Glutes
42%
Hamstrings
32%
Calves
22%
Legs (primary) — These fibres contribute to the movement, and they carry the majority of the load in this movement.
Glutes (secondary) — Assists by helping to extend and externally rotate the hip, contributing to hip power, posture and lower-back protection.
Hamstrings (secondary) — Assists by helping to bend the knee and extend the hip, contributing to hip power, sprinting and knee joint balance.
Calves (secondary) — Assists by helping to point the foot downward at the ankle, contributing to ankle stiffness, walking and jumping mechanics.
Benefits of the Bent Knee Back To Side Kick
Builds strength in the hamstrings through a squat pattern, which carries over directly to bending and straightening the knees and hips together.
Reinforces the quadriceps, glutes and trunk stabilisers as a coordinated unit rather than as isolated parts.
Uses bodyweight, which needs no equipment at all and can be done virtually anywhere.
How to Perform the Bent Knee Back To Side Kick
1
Set your starting position and brace your core before the first rep.
2
Break at the hips and knees together, keeping your weight through the midfoot.
3
Descend to a depth you can control with a neutral spine.
4
A good Bent Knee Back To Side Kick rep looks identical to the one before it; when it doesn't, the set is done.
5
Drive back up through the floor, keeping the hamstrings working the whole way.
6
Breathe out through the effort and keep the hamstrings under tension between reps.
Your Goal General Fitness
Sets
2–3
Reps
10–15
Rest
60s
Breathing Technique
The general rule for the Bent Knee Back To Side Kick is simple: inhale and brace at the top, exhale through the ascent. For heavier sets, take a breath in at the start position, brace as though bracing for a punch, and hold that pressure through the hardest part of the rep before exhaling. Consistent breathing is what keeps your brace intact from the first rep to the last.
Tips for Proper Form
Track the knees in line with the toes and keep the mid-foot loaded.
Set your position before the first rep rather than correcting it mid-set.
Keep the range of motion consistent across every rep so you can compare sessions honestly.
Keep the a lateral movement path deliberate rather than letting momentum carry it.
Control the lowering phase — most of the hamstrings stimulus comes from resisting the weight, not lifting it.
Break at the hips and knees together. Leading with the knees turns this into a quad-only movement and drops the glutes and calves out of it.
Log your Bent Knee Back To Side Kick numbers each session. The hamstrings responds to gradual, tracked increases far more reliably than to hard sessions you can't repeat.
Progress by changing leverage or tempo rather than adding reps forever — a slower rep loads the hamstrings more than ten fast ones.
Common Mistakes to Avoid
Letting the knees collapse inward as you stand up.
Do this insteadPush your knees out over your toes on the way up — cue it deliberately until it's automatic.
Treating the Bent Knee Back To Side Kick as a warm-up movement and never progressing it.
Do this insteadGive it real working sets — the hamstrings needs a genuine stimulus, not a token effort.
Letting the glutes compensate once the hamstrings tires.
Do this insteadStop the set at that point — past there you're training the compensation.
Variations by Experience Level
Beginner
Reduce the load and perform the Bent Knee Back To Side Kick for higher repetitions, focusing entirely on position rather than weight. Treat the Bent Knee Back To Side Kick as skill practice at this stage — the hamstrings adapts plenty from clean reps.
Intermediate
Increase total working sets before increasing load — volume drives most of the adaptation at this stage. Alternate harder and easier Bent Knee Back To Side Kick sessions rather than pushing every one.
Advanced
Progress to a heavier variation of the same pattern once technique is stable at your current load. Small, tracked increases on the Bent Knee Back To Side Kick beat occasional maximal efforts.
Safety Considerations
Warm up with lighter sets of the Bent Knee Back To Side Kick before your first working set.
The most common way the Bent Knee Back To Side Kick goes wrong is knees collapsing inward under fatigue.
Stop the set when technique degrades — a Bent Knee Back To Side Kick rep that no longer looks like your first one is not building anything.
Who Should Avoid This Exercise
The Bent Knee Back To Side Kick suits most healthy trainees, but it is not appropriate for everyone.
Anyone experiencing sharp, localised or radiating pain during the movement — that is a signal to stop, not to push through.
Anyone with an acute lower-back injury or disc irritation, until cleared to load the spine again.
This is general educational information, not medical advice. If you are managing an injury or medical condition, check with a qualified professional before adding this exercise to your programme.
What muscles does the Bent Knee Back To Side Kick work?
It primarily trains the legs, with the glutes, hamstrings, and calves assisting. The pattern is classified as squat, so the quadriceps, glutes and trunk stabilisers share the workload.
Is the Bent Knee Back To Side Kick suitable for beginners?
Yes. It is rated beginner-level, and the pattern can usually be learned in a single session with light resistance.
How many sets and reps should I do?
A practical starting point is 3 sets of 6-8, resting 2-3 min between sets, roughly 2x per week. Adjust from there based on how you recover.
What equipment do I need for the Bent Knee Back To Side Kick?
You need bodyweight. This needs no equipment at all and can be done virtually anywhere, though it is harder to load progressively once you outgrow it.
How do I breathe during the Bent Knee Back To Side Kick?
As a general rule, inhale and brace at the top, exhale through the ascent. Avoid holding your breath for the entire set.
What is the most common mistake with the Bent Knee Back To Side Kick?
Knees collapsing inward under fatigue. The simplest correction is to track the knees in line with the toes and keep the mid-foot loaded.
What can I do instead of the Bent Knee Back To Side Kick?
Good substitutes that train the same hamstrings pattern include Barbell Romanian Deadlift, Cable Pull Through, and Resistance Band Kneeling Leg Half Circle On Bench. Pick whichever matches the equipment you have available.
How often should I do the Bent Knee Back To Side Kick?
About 2x per week suits most people. Recovery, not frequency, is what limits progress.
About Training Your Hamstrings
Within hamstrings training, the Bent Knee Back To Side Kick is the bodyweight variation to reach for when you want a squat pattern you can repeat consistently.
The hamstrings run down the back of the thigh and perform two jobs: bending the knee and extending the hip. Strong hamstrings balance the quads, protect the knee, and are essential for sprinting and powerful hip extension.
Train them with two movement types. Knee-flexion work — lying and seated leg curls — targets the hamstrings directly, while hip-hinge movements like the Romanian deadlift, good morning, and Nordic curl load them through a powerful stretch. Combining both builds fuller, more resilient hamstrings than curls alone.
On hinges, push the hips back with a flat back and feel the stretch rather than rounding the spine. A slow lowering phase dramatically increases the training effect.