Lifting in Converse: The biomechanics, benefits, and risks of flat sole training

Converse-style zero-drop, incompressible flat soles can improve center-of-pressure stability and reduce energy loss from sole compression in deadlifts, but for squats they remove the 0.75 to 1 inch heel lift that helps ankle dorsiflexion. If mobility is restricted, that can increase knee and lumbar torque. Here is how to know when flat shoes are the right tool for your mechanics, and when a heeled lifter (or targeted mobility work) is the safer upgrade.

The relationship

Flat, incompressible shoes like Converse can increase perceived stability and reduce sole compression during heavy lifts compared with cushioned running shoes. The association between lifting in Converse and strength training dates back to the 1970s and 80s, when powerlifters realized that the thick, gel-filled soles of running shoes made heavy lifting feel less stable. The debate often centers on “flat vs. heeled,” but biomechanically, it is a question of ground reaction force and proprioception.

The primary appeal of Converse All Stars (Chuck Taylors) lies in their construction: a flat, relatively stiff rubber sole with zero heel-to-toe drop. In clinical terms, this is often grouped with “minimalist footwear” in the context of resistance training. Unlike running shoes, which are engineered to absorb impact through EVA foam or gel, lifting generally benefits from a shoe that resists compression. In a 2016 biomechanical analysis in the Journal of Strength and Conditioning Research, Whitting and colleagues reported meaningful footwear-related changes in squat mechanics across loads, supporting the idea that shoe construction can affect how force is expressed and controlled under the bar.^[1]

However, the relationship is not purely positive. While the flat sole can work well for the posterior chain mechanics of a deadlift, it can expose deficits in ankle mobility during squats. A standard Olympic lifting shoe has a hard heel raised by 0.75 to 1 inch. This artificial elevation allows the knee to track forward (dorsiflexion) without requiring extreme flexibility from the lifter’s ankle joint. By removing this heel lift, Converse demands that the athlete has enough anatomical range of motion to hit depth safely.

How it works

Understanding why lifting in Converse can work well requires looking at the physics of the foot-to-ground interface. There are three main mechanisms at play: Center of Pressure (COP) stability, force transfer efficiency, and kinetic chain alignment.

Center of Pressure and stability

Stability in lifting is defined by the ability to maintain the body’s center of mass over its base of support. In a 2012 study in the Journal of Strength and Conditioning Research, Sato and colleagues documented squat kinematic differences when lifters used weightlifting shoes, highlighting how footwear can change joint positions and control demands during the movement.^[2]

Converse shoes feature a thin, high-density rubber outsole that limits small shifts associated with soft foam compression. By keeping the foot closer to the ground (a low “stack height”), the moment arm between the ankle joint and the floor is reduced. This can lower the balance demands on lower-leg stabilizers and help the prime movers (quadriceps, glutes, hamstrings) express force more consistently.

Force transfer and Newton’s Third Law

Newton’s Third Law states that for every action, there is an equal and opposite reaction. In the context of the deadlift or squat, the “action” is the force the lifter drives into the floor. The “reaction” is the ground pushing back, which moves the weight up.

Cushioned shoes can act as dampeners. When force is applied, some energy goes into compressing the midsole rather than contributing to a stable base. In a 2017 study in the Journal of Sports Sciences, Legg and colleagues reported footwear-related differences in squat kinetics and kinematics, consistent with the practical observation that softer shoes can change force expression and bar path control under load.^[3] The hard rubber of a Chuck Taylor does not eliminate all losses, but it tends to reduce energy loss from sole compression compared with highly cushioned shoes.

Kinematics and ankle dorsiflexion

Kinematics refers to the geometry of motion. The “drop” of a shoe can alter lifting kinematics, and a raised heel artificially increases usable ankle dorsiflexion.

Dorsiflexion: The action of bending the foot upward toward the shin.

For a deep squat, the knees must travel forward past the toes. If a lifter wears Converse (0 mm drop) and lacks the flexibility to bend their ankles sufficiently, their body will compensate. Common compensations include the hips shooting backward or the lower back rounding (flexion) to maintain the center of gravity. This can shift demand away from the quads and toward the lumbar spine, potentially increasing shear stress on spinal tissues.

Conditions linked to it

While lifting in Converse is generally safe and often beneficial for deadlifts, using them inappropriately for squats or Olympic movements can exacerbate specific musculoskeletal conditions.

Plantar Fasciitis and Arch Strain: Converse offer minimal arch support. Under heavy loads (e.g., a 1RM squat), the foot arch may collapse excessively, a movement known as pronation. Repetitive collapse under load can strain the plantar fascia, the thick band of tissue connecting the heel to the toes. In a 2015 randomized controlled trial in Scandinavian Journal of Medicine & Science in Sports, Rathleff and colleagues found that high-load strength training improved outcomes in plantar fasciitis, underscoring that plantar tissues are load-responsive but can flare if progression is too aggressive.^[4]

Achilles Tendinopathy: For athletes accustomed to wearing shoes with a 10 to 12 mm heel drop in daily life, switching abruptly to a zero-drop shoe for loaded exercises can increase tension on the Achilles tendon. The tendon must elongate further to accommodate the flatter position, which can contribute to irritation if the tissue is not adapted.

Lumbar Strain (Lower Back Pain): As noted in the mechanics section, restricted ankle mobility in flat shoes often leads to a “good morning” squat pattern, where the chest collapses and the hips rise too fast. This lever arm can increase torque demands on the lumbar extensors and passive spinal tissues.

Symptoms and signals

Determining whether lifting in Converse is right for you requires monitoring your body’s feedback during compound lifts. Watch for these signals that suggest a flat shoe may be contributing to biomechanical breakdown:

Interpret the pattern, not just one cue. Heel lift and excessive forward lean often point to an ankle mobility limitation (or stance that demands more dorsiflexion than you have), while knee valgus can be a technique and strength issue that starts at the foot or hip, not only the shoe. If pain is sharp, progressive, or changes your movement on the fly, deload and get a form check from a qualified coach. If symptoms persist for more than one to two weeks, involve a clinician (such as a physical therapist) to rule out tendon or joint injury.

• Heel lift: Your heels unintentionally rise off the floor at the bottom of a squat. This indicates you have hit your anatomical end-range of ankle flexibility.
• Knee valgus (caving in): Your knees collapse inward as you push up from the bottom of a lift. While this can be a glute weakness, it often starts at the foot. The lack of arch support in Converse can allow the foot to roll in, dragging the knee with it.
• Excessive forward lean: You find it difficult to keep your torso upright during a back squat, forcing you to fold at the hips.
• Medial foot pain: Sharp or aching pain along the inside arch of the foot after a heavy session.

What to do about it

If you want to join the ranks of lifters using Converse, or if you are currently doing so and experiencing issues, follow this clinical progression to ensure safety and performance.

1. The Weight-Bearing Lunge Test (WBLT): Before squatting heavy in flats, test your ankle mobility. Place your foot 5 inches (approximately 12 cm) away from a wall. Keep your heel glued to the floor and try to touch your knee to the wall.
   
   Pass: Knee touches wall without heel lift. You have sufficient mobility for flat-shoe squatting.
   
   Fail: Heel lifts or knee cannot reach. You are a better candidate for heeled lifting shoes (squat shoes) while you work on mobility.
2. Match the Shoe to the Lift: You do not need to wear the same shoe for every exercise.
   
   Deadlifts: Converse are excellent here. The flat sole reduces effective pull height slightly and can help you feel more stable through the midfoot. Technique still matters, so keep the bar over midfoot and avoid letting your hips shoot up early.
   
   Low Bar Squats: Converse may work if you have passed the WBLT, as this style typically requires less forward knee travel.
   
   High Bar/Front Squats: These usually require more ankle dorsiflexion. Heeled weightlifting shoes are superior for many lifters here to help maintain a more upright torso.
3. Build “Foot Core” Strength: Because Converse lack arch support, your intrinsic foot muscles must do more work. Incorporate short foot drills. Pull the ball of your foot toward your heel without curling your toes to strengthen the arch. Start with lower volumes in Converse to allow your Achilles tendons and plantar fascia to adapt to the zero-drop position.

Bottom line

Converse are appropriate for deadlifts (and some low-bar squats) when you want a low, stable base and your mechanics stay clean. Heeled lifters are usually better for high-bar and front squats if ankle dorsiflexion is limited or you cannot hit depth without heel lift or excessive forward lean. If switching to flats triggers persistent foot, Achilles, knee, or back pain, reduce load and volume and get coaching or clinical evaluation.

References

1. Whitting JW, Meir RA, Crowley-McHattan ZJ, et al. Influence of Footwear Type on Barbell Back Squat Using 50, 70, and 90% of One Repetition Maximum: A Biomechanical Analysis. Journal of Strength and Conditioning Research. 2016;30:1085-92. PMID: 26349043
2. Sato K, Fortenbaugh D, Hydock DS. Kinematic changes using weightlifting shoes on barbell back squat. Journal of Strength and Conditioning Research. 2012;26:28-33. PMID: 22201687
3. Legg HS, Glaister M, Cleather DJ, et al. The effect of weightlifting shoes on the kinetics and kinematics of the back squat. Journal of Sports Sciences. 2017;35:508-515. PMID: 27096286
4. Rathleff MS, Mølgaard CM, Fredberg U, et al. High-load strength training improves outcome in patients with plantar fasciitis: A randomized controlled trial with 12-month follow-up. Scandinavian Journal of Medicine & Science in Sports. 2015;25:e292-300. PMID: 25145882