Single-Leg Heel Raises: How to Actually Load the Achilles

You're doing a hundred standing calf raises a day, and your calf size and ankle strength haven't budged in months. There's a reason for that. The moment you stand on two feet and lift your heels, your bodyweight splits automatically, roughly in half, across both legs. The load each ankle actually handles is only about half your bodyweight, which is less than what that same ankle absorbs from a single ordinary walking step. The body is honest about this: without a stimulus clearly above what it already handles during everyday walking and running, it has no reason to build the muscle or stiffen the tendon any further. That's usually the real reason a plateau on two-leg calf raises never breaks, no matter how many reps you grind out.

The fix is simple but unfamiliar at first. Stand on one leg and lift your entire bodyweight through that single ankle. The load the Achilles tendon and calf muscles have to handle nearly doubles in that instant, and since you also have to hold your own balance, the demand on your nervous system climbs right along with it. Most people who try this the first time can't hold it for more than a few reps before the heel wobbles sideways, or the resting foot quietly presses into the floor to help out without them noticing.

This is a different axis entirely from the seated calf raise, where you sit with the knee bent to isolate the soleus. The seated version is about choosing which muscle does the work by changing knee angle. The standing single-leg version covered here keeps the knee straight and drives the total amount of load up by shifting your entire bodyweight onto one ankle. The two exercises aren't competing with each other, they fill different gaps, and if soleus endurance is what you're after, it's worth reading alongside this seated calf raise piece.

If your Achilles is already painful and you need to tread carefully, the heel raise progression guide built around eccentric heel drops is the safer place to start. This guide is written for someone free of pain who wants to raise the ceiling on what their ankle can actually handle, or who wants to prep the ankle ahead of hiking, running, or jumping. It walks through the basic setup for a balance point, the stage that shifts load from two legs to one, the stage that opens the range of motion fully on a stair edge, and finally the stage that finishes the job with external load and tempo, laid out over 8 weeks.

Why a Two-Leg Calf Raise Under-Loads the Achilles: The Truth About Load Distribution

When both feet are planted on the floor, bodyweight is physically split between two contact points. It isn't always exactly even, but roughly half your bodyweight lands on each ankle, and the moment you lift the heels, the load the gastrocnemius, soleus, and Achilles tendon on that ankle have to handle is set at that same rough level. The problem is that this load sits below what the body already handles in ordinary daily movement.

Komi, Fukashiro, and Järvinen (1992, Clinics in Sports Medicine) implanted a force-measuring device directly at the ankle to record the actual force running through the Achilles tendon during walking and running, and reported that ordinary walking alone puts roughly 2.6 to 4 times bodyweight through the tendon, while running pushes that up to roughly 4 to 7.7 times bodyweight. The key point is that these figures occur during the single-leg support phase of each step. In other words, plain walking already repeatedly exposes the Achilles tendon to several times bodyweight in force, while a two-leg calf raise done at roughly half bodyweight per ankle doesn't even reach that everyday baseline. The limitation is that this study required invasive implantation, so the number of subjects was extremely small, and individual variation was large enough that the exact multiplier can't be applied uniformly to everyone. Even so, the direction of the finding, that single-limb support movements like walking and running demand far more force than two-leg support movements, has been repeatedly confirmed by other measurement approaches since.

The body reflects this difference honestly. Muscle and tendon only remodel their structure when a new stimulus arrives clearly above what they're already repeatedly exposed to. No matter how many reps of a two-leg calf raise you grind through at a load already lower than walking, there's simply no reason for the body to adapt further. Stand on one leg and lift instead, and the load that single ankle handles jumps straight up to roughly full bodyweight, and once you factor in movements that add speed or landing impact, such as descending stairs two at a time, changing direction, or a light jump landing, the load gets meaningfully closer to the same order of magnitude as walking or running.

If you want a rough read on where your own ankle stands right now, there's a simple self-test. Rest your fingertips lightly against a wall or doorframe for balance, stand on one leg with the knee straight, and count how many clean heel raises you can do without bouncing before form breaks down. Lunsford and Perry (1995, Physical Therapy), in their study of the standing heel-rise test, reported that healthy young adults averaged somewhere in the upper 20s for reps, while older adults dropped to roughly the low teens. The limitation here is a modest sample, healthy subjects only, and a single test session, so applying these numbers directly as a clinical threshold for someone in pain or in rehab is a stretch. But as a rough gauge of your current level, and as a way to track change once you finish the program, the test holds up well. Run it before you start this program and again after 8 weeks, and compare the numbers directly.

Start With the Setup: A Balance Point and Load-Shifting Adaptation

Before jumping straight into a bodyweight single-leg raise, pick a fixed point to balance against. Stand where you can rest your fingertips lightly on something stable that won't move, such as a wall, doorframe, or the edge of a table. Make it clear to yourself from the start that this hand contact is a safety pin for a sideways wobble, not something to pull or push yourself up with. The moment you start loading weight into your hand, the ankle load drops off and the whole point of the exercise disappears.

Stage 1: Load-Shifting Adaptation Drill

Starting Position Stand barefoot with both feet together. Rest your fingertips lightly on the balance point and slowly shift your weight onto the working leg, leaving the resting foot's toes barely grazing the floor. Find the point where roughly 80 to 90 percent of your weight sits on the working leg.

Movement Steps (1) Press the ball of the working foot into the floor and lift the heel as high as it will go. (2) Hold the top for 1 to 2 seconds and check that the ankle isn't collapsing inward or outward. (3) Lower slowly over 3 seconds, reversing direction just before the heel touches down fully. (4) Finish the prescribed reps, then switch legs and repeat the same sequence.

Breathing Exhale briefly on the lift and inhale slowly through the nose across the 3-second lowering phase. It's common to unconsciously hold your breath while chasing balance, and holding your breath sends tension into the shoulders and neck before it ever reaches the ankle.

Sets, Reps, Frequency 12 to 15 reps per side for 3 sets, resting 30 to 45 seconds between sets. For the first 1 to 2 weeks, aim for 4 sessions a week while you focus purely on learning the feel of weight shifted onto one side.

Common Mistakes and Fixes The most common error is the resting foot quietly pressing into the floor to help, well past what balance requires. That foot's toes should only just graze the floor, and if that's hard to control, lifting the resting knee slightly forward so the foot comes off the ground entirely gives you an honest read on the actual stimulus. Gripping the balance point hard and pulling yourself upward with it is another common mistake — keep light fingertip contact but cut the force in half. Letting the hip shift away from the working leg so the whole torso tilts is a third, and correcting it means squaring the hips back toward the balance point as if pointing your navel at it.

Stop If You Notice A sharp pain right at the Achilles insertion, or any new numbness or radiating pain into the sole or toes, means stop immediately. If the ankle suddenly buckles sideways and gives out, end the session for the day, and if the same thing happens again the next session, get the ankle's stability checked before continuing.

A meaningful left-right gap often shows up from day one. A leg with a history of standing lopsided or a past ankle sprain tends to struggle noticeably more with balance and leans harder on the balance point within a few reps. Train the weaker side first, and the wider the gap grows relative to the stronger side, the more it helps to add one extra set to the weaker leg to close it back down.

Adding Load in Order: From a Full Single-Leg Raise to External Weight

Stage 2: Move to a Full Single-Leg Heel Raise

Progression Criteria Once you can complete 15 reps per side for 3 sets in Stage 1 with roughly 80 to 90 percent of your weight on the working leg, no bouncing, and no help from the resting foot pressing into the floor, move on.

Starting Position Lift the resting foot fully off the floor and tuck the knee back slightly. Rest only fingertips on the balance point, and let the working leg alone support the entire bodyweight.

Movement Steps (1) Press the ball of the foot into the floor and lift the heel as high as it will go. (2) Hold for 2 seconds at the top. (3) Lower slowly over 3 to 4 seconds. (4) Reverse direction just before the heel touches down fully and continue into the next rep.

Breathing The exhale-on-lift, inhale-on-lower rhythm is the same as Stage 1, but since you're now supporting the entire bodyweight alone, pay closer attention to not holding your breath during the top-position hold.

Sets, Reps, Frequency 10 to 12 reps per side for 3 sets, 3 to 4 times a week. Once flat-ground reps feel comfortable, moving the range of motion to a stair edge, where only the toes make contact, opens the stimulus starting from a stretched Achilles position and raises the total training load another notch. Switch to the stair-edge version once you can clear 15 reps for 3 sets on flat ground with room to spare.

Common Mistakes and Fixes With the full bodyweight now on one foot, weight commonly drifts toward the outside or inside edge of the ball of the foot. Correct it by bringing weight back under the big toe and second toe. On the stair edge, dropping the heel too quickly can produce a sharp jab of pain low in the Achilles — slow the descent to half speed through the stretched position.

Stop If You Notice A stabbing pain in the tendon itself when lowering on the stair edge means reduce the range of motion and go back to the flat-ground version. If the ankle suddenly rolls as if about to sprain, stop that set immediately.

Stage 3: Finish the Load With External Weight and Tempo

Progression Criteria Once you can clear the stair-edge version for 12 reps per side for 3 sets with no pain, move to the final stage. This stage exists for anyone bodyweight alone no longer challenges — if the stair-edge version is still genuinely hard on its own, there's no need to rush here.

Starting Position Load a backpack evenly across both shoulders with water bottles or books, or hold a dumbbell in each hand. Start from the same stair-edge position used in Stage 2.

Movement Steps (1) With the load on, press the ball of the foot into the stair edge and lift the heel as high as it will go. (2) Hold for 1 to 2 seconds at the top. (3) Lower slowly over 4 to 6 seconds to the stretched position. (4) Move straight into the next rep as the slow lowering phase ends.

Breathing Breathing tends to get shallow as load increases. Exhale briefly on the lift, and across the 4 to 6 second lowering phase, keep breathing going in two or three short breaths rather than holding it.

Sets, Reps, Frequency 8 to 10 reps per side for 3 sets, 3 times a week. Start with a load of roughly 5 to 10 percent of bodyweight, around 3 to 7 kilograms, and only add 500 grams to 1 kilogram once you can clear 10 reps for 3 sets comfortably at the current load.

Common Mistakes and Fixes The urge to add load faster sometimes leads people to speed up the lowering phase, which cuts the time the tendon spends under stretch and lowers the quality of the stimulus — holding that 4 to 6 second descent matters more than adding weight. Leaning the torso forward under load is another common issue; tighten the pack straps and keep your eyes forward to keep the torso upright.

Stop If You Notice A new burning pain in the tendon during the lowering phase, or pain that's still clearly present the next day, means reduce the load or drop back to Stage 2. Pain that seems to shift toward the knee or hip is a sign the load is too heavy — reduce it immediately.

Pairing added weight with a slow lowering phase follows the same principle behind what strength training commonly calls heavy, slow resistance work. Kongsgaard and colleagues (2009, Scandinavian Journal of Medicine and Science in Sports) compared eccentric training against this kind of progressive, heavy slow resistance training in patients with chronic Achilles tendinopathy over 12 weeks, and found both approaches produced similar improvements in pain and function, with the heavy slow resistance group showing a slight edge in tendon structural change and training satisfaction. The limitation is that group sizes were modest and the study compared the two methods head-to-head without an untreated control group, so it can't show the pure effect size of either method against doing nothing at all. For someone free of pain aiming at prevention and performance, this same principle of layering load beyond bodyweight applies directly to this third stage.

An 8-Week Program: Weekly Targets

The table below is only an example of an average pace. If you haven't cleared a stage's progression criteria, repeat that week rather than moving on.

If you're still on Stage 2 after 8 weeks, that isn't a failure. A past ankle sprain or a wide starting gap in left-right balance can easily stretch this out to 10 to 12 weeks, and that's not unusual. Sticking to each stage's progression criteria in order matters more than finishing on a fixed schedule for building load without injury.

The self-test covered earlier is also worth reusing to gauge your pace. Record how many clean, bounce-free single-leg reps you could do before starting the 8-week program, then count again the same way once you finish. If rep count went up and the left-right gap narrowed along with it, the program did its job. If reps went up but the gap stayed the same or widened, add an extra set to the weaker side specifically to close that gap.

When to Avoid This: Contraindications and Stop Signals

This program is built for someone free of pain who wants to raise the real load ceiling their ankle can handle. It is not a substitute for care in the case of an acute injury or a condition that needs a diagnosis. See an orthopedist or physical therapist first if any of the following apply.

• A suspected or confirmed Achilles tendon rupture within the recent past, or a post-surgical period before your surgeon has cleared weight-bearing load
• A recent ankle sprain with swelling or bruising still present, not yet past the acute phase
• Existing pain at the Achilles insertion or mid-tendon that shows up even during ordinary walking — in this case, the heel raise progression guide built around eccentric heel drops is the safer place to start instead of this one
• Sudden swelling, warmth, and severe localized tenderness in one calf that raises suspicion of deep vein thrombosis — in this case, seeing a doctor immediately takes priority over any exercise
• An ankle fracture where the bone has not yet fully healed
• Dizziness or a balance disorder that makes standing unsupported on one leg genuinely unsafe
• Diabetic peripheral neuropathy or another condition that has significantly reduced sensation in the sole of the foot, making it hard to feel pain signals in time

Even if none of the above applies, stop immediately and monitor your condition if you notice any of the following during exercise: a sharp pain at the Achilles insertion or mid-tendon, a popping sound or sensation at the back of the heel followed by a sudden loss of strength, new or worsening numbness or radiating pain into the sole or toes, or sudden swelling of the whole leg paired with warmth. The second sign should raise suspicion of a tendon rupture, meaning you should stop exercising entirely on the spot and get emergency care, and the last sign could indicate deep vein thrombosis and should be checked at a hospital right away rather than watched for a day or two.

If even Stage 1's load-shifting drill is hard to hold for more than a few seconds without hand support, or if balance keeps collapsing on one specific side week after week, the cause may not be simple weakness — it could be chronic ankle instability or a nerve issue. In that case, having a physical therapist check ankle stability first will save more time than pushing through the program alone.

Near-infrared LED is not a substitute for this exercise, nor is it a medical device that directly treats tendon injury — think of it as a wellness tool that supports recovery around your training. Never shine it directly into the eyes, and consult your physician first if you're taking a photosensitizing medication. As a rule, don't apply it directly over open wounds or areas with reduced sensation. For a narrow, deep area like the Achilles and calf, many users keep the device 5 to 15cm from the skin for 10 to 15 minutes per session, 3 to 5 times a week, though the right duration varies by skin condition and individual factors.

Whatever stage you're on, grinding through pain to add reps or weight is off the table. The load an ankle can handle builds up gradually over weeks — it isn't something you can force higher in a day or two. When in doubt, default to lowering the load and rebuilding reps and form first.