Ice or Heat for Knee Pain (and Shoulder Pain): Which Is Better?

01Rule

The basic rule

• Ice: new injuries (first 48–72 hours), swelling, warmth, acute flare-ups, after exercise if the joint is irritated.
• Heat: stiffness, long-standing aches, osteoarthritis, muscle tension, before stretching or exercise.
• Either: general soreness; choose what feels better.
• If unsure, start with cold after an injury and heat for stiffness without swelling.

02Ice

How ice works and how to use it

Cold narrows blood vessels, which may reduce swelling and bleeding into tissues, and slows nerve conduction, which reduces pain. Use a cold pack, ice in a damp cloth, or a bag of frozen peas wrapped in a towel. Apply for 15–20 minutes, then remove for at least an hour; the NHS suggests up to 20 minutes every two to three hours in the first days after a sprain or strain. A systematic review of ice for soft-tissue injuries found limited evidence overall, but suggested ice may be more effective when combined with exercise and applied in repeated short sessions.

03Heat

How heat works and how to use it

Heat increases blood flow, relaxes muscles and makes tissues more flexible, which helps reduce stiffness and aching. Use a hot water bottle wrapped in a cover, a microwavable heat pack, a warm bath or shower, or a heat wrap. Apply for 15–20 minutes at a comfortable warmth. A review of heat and cold therapy found that heat can reduce pain and improve function in some musculoskeletal conditions, such as acute low back pain.

04Knee

Ice or heat for common knee problems

• New knee sprain or knock: ice for the first few days.
• Knee osteoarthritis: heat for morning stiffness; ice if the knee is swollen and warm during a flare.
• Runner’s knee after a run: ice for short-term relief; see runner’s knee.
• Tendon pain: either for comfort; exercise is the main treatment.
• After knee replacement: cold therapy is commonly used to manage swelling; see knee replacement recovery.
• Tight muscles around the knee: heat before stretching.

05Shoulder

Ice or heat for shoulder pain

• Acute shoulder strain or flare of tendon pain: ice for short-term relief.
• Frozen shoulder and stiffness: heat before gentle stretching exercises; see frozen shoulder.
• Neck and shoulder muscle tension: heat.
• After shoulder surgery: follow your surgeon’s advice; cold is often used early.

06Alternate

Can you alternate ice and heat?

Some people alternate cold and heat (contrast therapy), particularly after the initial swelling phase. Evidence for added benefit is limited, but it is generally safe if each is applied for short periods and the skin is protected. Many people simply use the option that feels best at the time.

07Safety

Safety tips

• Always wrap ice or heat packs; never apply directly to skin.
• Limit each session to 15–20 minutes.
• Check the skin regularly for redness, blisters or numbness.
• Avoid using ice or heat on areas with poor sensation, poor circulation or broken skin.
• Take extra care if you have diabetes, Raynaud’s phenomenon or vascular disease.
• Do not fall asleep on a heat pad or electric blanket.
• Do not use heat on a swollen, hot joint.

08Other

Beyond ice and heat

Ice and heat relieve symptoms but do not fix the underlying problem. For most knee and shoulder pain, staying active, specific strengthening and mobility exercises, managing load and, where needed, pain relief are the key treatments. The NHS advises seeing a GP if knee pain does not improve within a few weeks or is severe.

09Cases

Three common situations

• Twisted knee playing football, now swollen: ice, rest, compression and elevation for the first days; see a doctor if you cannot bear weight.
• Stiff, achy knees in the morning with arthritis: a warm shower or heat pack before moving.
• Stiff shoulder after weeks of reduced use: heat before stretching exercises.

10Make

Making your own cold and heat packs

• Cold pack: a bag of frozen peas or sweetcorn moulds well around the knee; refreeze and label it so it is not eaten.
• Wet towel cold pack: a damp towel in a plastic bag, frozen for 15 minutes.
• Rice heat pack: uncooked rice in a cotton sock, warmed briefly in the microwave; test the temperature first.
• Warm towel: soaked in warm water and wrung out.
• Commercial gel packs are reusable and convenient.

11Exercise

Using ice or heat around exercise

Heat before exercise can loosen stiff joints and muscles, making it easier to move, which is useful for people with arthritis. After exercise, ice can ease short-term soreness in a joint that tends to flare. Routine icing after every workout is not necessary for most people and may slightly blunt training adaptations in athletes. Use whichever helps you stay active.

12Summary

Key points to remember

• Ice for new injuries and swelling.
• Heat for stiffness, arthritis and muscle tension.
• Apply for 15–20 minutes, always wrapped.
• Exercise and load management are the main long-term treatments.