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

For decades, the humble Chuck Taylor has been the unofficial footwear of powerlifting. But while flat shoes offer superior stability for deadlifts, biomechanical evidence suggests they may not be the universal fix for every lifter’s squat technique.

The relationship

Walk into any serious powerlifting gym, and you will see as many pairs of canvas sneakers as you do expensive weightlifting 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 were detrimental to moving heavy iron. 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, incompressible rubber sole with zero heel-to-toe drop. In clinical terms, this is referred to as “minimalist footwear” in the context of resistance training. Unlike running shoes, which are engineered to absorb impact through EVA foam or gel, lifting requires a shoe that resists compression. When a lifter drives their foot into the floor during a squat or deadlift, any compression in the sole represents a “leak” of energy that should have gone into moving the barbell.^[1]

However, the relationship is not purely positive. While the flat sole is ideal for the posterior chain mechanics of a deadlift, it exposes 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 possesses widely available anatomical range of motion to hit depth safely.

How it works

Understanding why lifting in Converse is effective 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. Research indicates that softer soles introduce “micromovements” as the foot attempts to stabilize on the compressing foam. This increases the sway of the Center of Pressure (COP).^[2]

Converse shoes feature a thin, high-density rubber outsole that limits these micromovements. 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 minimizes the torque required by the stabilizer muscles of the lower leg to maintain balance, allowing the prime movers (quadriceps, glutes, hamstrings) to generate maximal output.

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 act as dampeners. When force is applied, a percentage of that energy is used to compress the foam mid-sole rather than being returned as ground reaction force (GRF). A study comparing running shoes to flat-soled shoes found that peak force production and the rate of force development were significantly blunted in cushioned footwear.^[3] The hard rubber of a Chuck Taylor provides a non-compressible surface, ensuring near 1:1 force transfer.

Kinematics and ankle dorsiflexion

Kinematics refers to the geometry of motion. The “drop” of a shoe drastically alters lifting kinematics. A raised heel artificially increases ankle dorsiflexion range of motion.

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 (0mm drop) and lacks the flexibility to bend their ankles sufficiently, their body will compensate. The most common compensation is the hips shooting backward or the lower back rounding (flexion) to maintain the center of gravity. This shifts the load from the quadriceps to the lumbar spine, potentially increasing shear force on the vertebrae.

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.^[4]

Achilles Tendinopathy: For athletes accustomed to wearing shoes with a 10-12mm heel drop in daily life, switching abruptly to a zero-drop shoe for loaded exercises places increased tension on the Achilles tendon. The tendon must elongate further to accommodate the flat position, which can lead to inflammation or strain 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 places significant torque on the lumbar extensors and discs.

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 causing biomechanical breakdown:

• 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 cause the foot to roll in, dragging the knee with it.
• Excessive forward lean: You find it impossible 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 (approx. 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 the distance the bar must travel and keeps you back on your heels.

Low Bar Squats: Converse may work if you have passed the WBLT, as this style requires less forward knee travel.

High Bar/Front Squats: These require maximum ankle mobility. Heeled weightlifting shoes are superior for most people here to maintain vertical torso alignment.

3. Build “Foot Core” Strength

Because Converse lack arch support, your intrinsic foot muscles must do the work. Incorporate “short foot” exercises—pulling 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

Lifting in Converse is more than a retro trend; it is a biomechanically sound choice for exercises requiring maximum stability and minimal range of motion, specifically the deadlift. The hard, flat rubber sole facilitates efficient force transfer and ground connection. However, for deep squatting, the lack of heel elevation can expose mobility deficits that lead to poor posture and injury risk. The decision to wear them should be based on your ankle dorsiflexion ability and the specific lift you are performing, rather than brand loyalty.

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