If you follow Anna Sitar's recent Miami run recap, you already know how a run can go from hero to zero.
One minute, we’re rocking our yellow matching run sets, and next, she's calling a walk break mid-run with the Happy Pace Run Club.
Shin pain (cry). The uninvited guest that ruins more training blocks than anything else.
While her Substack comments chatted about the importance of sleep positions and heel raises, the sports medicine world has also been debating a big question: what we've long called "shin splints" or "medial tibial stress syndrome (MTSS)" should be renamed and rehabbed differently.
The old rule was to rest until it stops hurting. The new rule: you can keep going, but only if you follow a very specific set of protocols.
This is our breakdown, including why Anna's “super shoe” swap was most likely the real culprit, and a renamed approach that some physios in the sports medicine world are currently debating.
Before we get into it: I'm a science nerd who reads the British Journal of Sports Medicine for fun — not a doctor, not your physio. Bone stress injuries are serious — an ignored stress fracture can become a complete break requiring surgery. Everything here is educational. If you have pain at rest, pain that makes you limp, or severe point tenderness, go see a sports medicine doc before trying any of this.
"Super Shoe Withdrawal" Is a Real Thing
Anna substacked her backstory that she'd been running (and loving) in the New Balance SC Elites (a carbon-plated super shoe) exclusively and switched to a more standard running shoe to “save them”.
That swap is almost certainly what might have triggered the pain.
Carbon plates act as a rigid lever, improving running economy by doing a significant portion of the mechanical work your muscles would otherwise handle. Specifically, they reduce the demand on the soleus (your deep calf muscle) and the toe flexors during push-off. Run in carbon-plated shoes exclusively, and your soleus progressively adapts to a lower workload (because the plate's stiffness is generating a large part of your propulsive force).
Switch back to a flexible standard trainer, and the soleus is suddenly managing a load it hasn't been fully primed for in months. Because the soleus attaches directly to the tibial fascia, when it's abruptly overloaded, it pulls excessively on the connective tissue of the shin — triggering the characteristic diffuse medial pain. It wasn't the Miami heat. It was most likely her footwear transition.
Science Just Renamed Shin Splints — and the New Name Is Unfortunate
"Shin splints" was always too vague, and "medial tibial stress syndrome" (MTSS) swung too far the other way, sounding scary and like a diagnosis that requires six weeks off and a walking boot.
The problem some professionals have with MTSS is that it implies actual bone damage. But imaging research shows plenty of people with real pain and no structural damage, and plenty of people with structural changes and zero pain. The label was doing more harm than good.
The proposed new term is LIMP — Load-Induced Medial-Leg Pain. Yes, the acronym is unfortunate. We know. But the concept behind it actually makes sense.
Load-induced means it's a response to a training load your tissue wasn't ready for — a spike in volume, intensity, or a change in footwear — not a sign that something is structurally broken.
Pain means it's a nociceptive signal your body uses to flag excess load. It's not a diagnosis of structural damage.
Why does renaming it matter? Because a name that sounds like your bone is breaking often triggers complete rest, which most of the time actually weakens the tissue. LIMP, AKA "you have a load management issue", means you can fix it while still running. Win-win.
About That Stomach Sleeping Comment
One commenter suggested her coach blamed stomach sleeping for shin splints. Is there anything to it?
Sort of — but don't stress about it.
Stomach sleeping keeps your feet in a more pointed position (plantarflexion) for 6 to 8 hours. That can shorten your calf muscles overnight, which potentially might reduce your ankle's range of motion. Reduced ankle mobility is a legitimate risk factor for shin pain — if your heel lifts too early in your stride, your tibia absorbs more impact than it's built for. But whether sleeping on your stomach is the actual cause, or just one minor contributor? Hard to prove, and probably not your main issue.
If you want to try the old coach trick, they might suggest sleeping far enough down in the bed that your feet hang off the edge, keeping your ankles neutral. No scientific backing, but if you want to change things up, we guess it costs nothing, and your calves might (but probably won’t) feel better in the morning.
The Three Red Flags: When to Stop and See Someone
Before trying to manage this yourself, rule out a stress fracture with these home checks.
The Press Test
Run your finger slowly along your shin bone. Diffuse pain across a broad area (5cm or more) that feels like a bruise = likely LIMP, soft tissue irritation. One specific point — coin-sized, makes you flinch — is a classic stress fracture sign. Stop running and get imaging.
The Night Pain Test
Does your shin throb when you're lying still doing nothing? Pain at rest is a red flag for bone pathology. LIMP only hurts under load.
The Hop Test
Hop 10 times on the affected leg on a hard surface. Sharp, shooting pain that stops you mid-hop means your bone is not ready for impact. Don't push through it.
The Rehab Protocol (Based on the 2025 Delphi Consensus)
If you've passed all three checks and have been seen by a clinician, here's the current evidence-based approach from Hoenig et al. (2025) for keeping you moving while you heal. This is what a physio who's up to date should be working from — but every case is different, so use it as a conversation starter, not a prescription.
Step 1
The 24-Hour Rule
This is the part that surprises most runners: you don't have to stop completely. Running with mild discomfort — up to a 3 out of 10 — is generally acceptable.
The metric that actually matters is the next morning. If you wake up and it's worse than yesterday, you exceeded your capacity — dial back the distance or pace. If it's back to baseline, you're adapting. That's the feedback loop you're managing.
Step 2
Two Biomechanical Adjustments
These reduce load on the tibia without you having to stop running:
Increase your cadence by 5–10%. A higher step rate reduces vertical load rate and peak tibial stress per stride. Think quick, light turnover — shorter ground contact time, not bigger push-off.
Shorten your stride. A foot strike that lands in front of your center of mass increases braking force and shifts load onto the anterior shin. Moving your foot strike closer to under your hips reduces that impact.
Step 3
Train the Soleus Specifically
The commenter who suggested heel raises was on the right track — but the type of raise matters.
Straight-leg calf raises → gastrocnemius (the big surface muscle)
Bent-knee calf raises → soleus (the deep muscle that's usually the problem)
The actual prescription: seated calf raises with heavy weight, knees at 90 degrees. The goal is to condition the soleus to handle the load so the shin bone doesn't have to absorb it.
Anna's pain was almost certainly super shoe withdrawal — a load her calves weren't ready for. The good news is that LIMP is usually a load management problem, which means it has a load management solution. Pass the hop test, follow the 24-hour rule, and do the heavy seated calf raises. You'll be back before the next run club meetup.
xx, Athlete Girl
