PUT THE ICE DOWN

Root Strength · Training Notes No.1

PUT THE
ICE DOWN.

ICE or HEAT? What the research really says.

You tweaked something under the bar — ice it, right? Not so fast. The old rulebook on ice and heat got rewritten, and grabbing the wrong one at the wrong time can stall the comeback you're chasing. Here's what the research actually says — and how to train around it.

Georgetown, Seattle7 min readEvidence-based
ICE[ COLD ]
Constricts · Numbs · Slows
Fresh injuries, first 24–48 hours
Short-term pain relief only
Calming an acute flare-up
Numbing sharp, localized pain
HEAT[ WARM ]
Dilates · Relaxes · Loosens
Chronic stiffness & tightness
Muscle aches & spasms
Warming up before activity
Ongoing pain with no swelling

It's one of the most common questions we get at Root Physical Therapy: "Should I ice it or heat it?" For decades the answer seemed simple — ice for injuries, heat for stiffness. But the research has shifted, and some of what you grew up believing is now considered outdated, or even counterproductive.

01The Rule That Got Benched

For 40 years, the reflex was RICE — Rest, Ice, Compression, Elevation. It came from a 1978 book by Dr. Gabe Mirkin and became gospel in every locker room and training room. There's just one problem: in 2015, Dr. Mirkin himself walked it back.

// The reversal
Old belief
Ice speeds healing — keep icing for days.
What the evidence says
Ice is a pain tool, not a healing tool.
A 2024 critical review in the British Journal of Sports Medicine found no human evidence that icing improves tissue regeneration — and animal studies suggest prolonged icing may actually delay muscle healing.

Here's why the thinking changed. When you ice, blood vessels constrict — that numbs pain and limits swelling, which feels like progress. But the inflammatory response you're shutting down isn't a malfunction. It's your body's repair crew clocking in. Inflammation is how white blood cells, growth factors, and satellite cells reach the injury to rebuild it. Suppress it too hard, too long, and you can slow the very healing you're chasing.

1978
RICE introduced — now outdated
2015
Its creator reversed his stance
10–20
Minutes max per session, pain only
02So Do You Ice Or Not?

Yes — but with a purpose and a timer. Ice is genuinely useful for short-term pain relief in the first day or two after an acute injury. The mental shift is understanding what it's for: managing symptoms, not accelerating repair.

// Ice, done right

Apply for 10–20 minutes, wrapped in a towel (never bare on skin), during the first 24–48 hours after an acute injury. Use it for pain, then move. Most people should transition from ice to gentle active rehab within 48–72 hours.

03What Replaced RICE

The framework that has largely taken over is PEACE & LOVE (introduced in the BJSM in 2019). It moves the focus from passively resting and icing toward protecting early, then loading and moving — because movement, not cold, is what drives recovery.

P E A C ERight after injury
PProtectEase off activities that sharply spike pain for the first few days.
EElevateRaise the limb to help drain swelling.
AAvoid anti-inflammatoriesThey may blunt the natural healing signal.
CCompressUse compression to manage swelling.
EEducateKnow that your body often heals without passive gadgets.
L O V EThe days after
LLoadReturn to activity gradually — loading tissue drives repair.
OOptimismConfidence and mindset genuinely shape outcomes.
VVascularizationPain-free cardio pushes blood to healing tissue.
EExerciseRebuild strength, mobility, and function with movement.
04When Heat Wins

Heat runs the opposite direction from ice: it opens blood vessels, lifts circulation, relaxes muscle, and improves tissue elasticity. Wrong for a fresh, swollen injury — right for stiffness and chronic aches.

! Never do this

Never put heat on a fresh injury that's actively swelling. Heat drives more blood to the area, which makes swelling and inflammation worse in the acute phase. Wait until the initial swelling settles — usually after 72 hours.

Heat is at its best for chronic muscle tightness, arthritis stiffness, and warming up before activity or rehab. A common clinical move: heat before your exercises, when stiffness is the thing holding you back. The warmth lowers pain sensitivity and quiets muscle guarding, so you can move through the work that actually helps.

// Heat, done right

Use warm — not hot — heat for 15–20 minutes. Moist heat (a damp warm towel or moist pad) penetrates deeper than dry. Apply before movement or to unwind at day's end. Skip it on open wounds, numb areas, or anything actively swollen.

05The 10-Second Call

Standing at the freezer, unsure? Run these three questions.

// decision engineIce or Heat?
Q1Did it just happen? (last 48 hrs)
Yes → Ice
10–20 min for pain relief
No → Heat
Especially if it's stiff
Q2Active swelling, redness, or warmth?
Yes → Ice
Or just elevate & compress
No → Heat is safe
Once swelling is gone
Q3Just stiff, achy, or tight — not injured?
Yes → Heat
Relaxes and loosens tissue
Warming up → Heat
Before activity or rehab
06The Bottom Line

Neither ice nor heat is a healing shortcut. Both are tools for managing symptoms so you can do the thing that genuinely drives recovery: move. Ice buys early pain relief. Heat loosens you up to work. But the real medicine is loading the tissue, restoring movement, and rebuilding strength — which is exactly what physical therapy is built to do.

Keep This Somewhere
IceFresh injury, first 24–48 hrs, 10–20 min, pain only.
HeatChronic stiffness, aches, pre-training warm-ups — never on fresh swelling.
BothManage symptoms; neither speeds healing on its own.
TruthInflammation isn't the enemy — it's how you heal.
RuleMovement is the medicine. PEACE & LOVE, not RICE.
07When To Call In A Pro

Ice and heat are fine for everyday tweaks. But if pain is significant, isn't improving after a few days, changes how you move, or keeps coming back — that's the tissue telling you it needs more than a heating pad. Pushing through it under load usually makes it worse, not tougher.

That's the advantage of training at Root Strength: when something goes sideways, Root Physical Therapy is on-site in the same building. Our PTs can assess the injury, get you loading again safely, and build the return-to-training plan — no referral needed in Washington. Same roof, same team, straight back to the bar.

General guidance based on current research — not individualized medical advice. If you have a serious injury or a condition affecting circulation or sensation, check with a healthcare professional before using ice or heat.

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// sources
  1. Dubois B, Esculier JF. Soft-tissue injuries simply need PEACE and LOVE. British Journal of Sports Medicine. 2020;54(2):72–73.
  2. Critical review of cryotherapy and tissue regeneration. British Journal of Sports Medicine. 2024.
  3. Mirkin G. Revised position statement on ice and injury recovery, 2015.
  4. Wang ZR, Ni GX. Is it time to put traditional cold therapy in soft-tissue rehab out to pasture? World Journal of Clinical Cases. 2021;9(17):4116–4122.
  5. Malanga GA, Yan N, Stark J. Mechanisms and efficacy of heat and cold therapies for musculoskeletal injury. Postgraduate Medicine. 2015;127(1):57–65.
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