When one gets an injury, such as happens playing sports, one of the treatments is to put ice on the injury. This is to suppress swelling of the injured part. How long is this an effective way of reducing swelling? Is there some point at which ice no longer does any good?
The page below says 2-3 days (48-72 hours) for ice therapy then switch to heat therapy:
As long as the body part in question wants to swell, putting cold on it is helpful. You want cold enough to stop swelling without stopping circulation altogether or causing frostbite.
Now ice itself gets warm. So you need to renew the ice regularly to keep applying cold to the affected area until the swelling stops trying to happen.
Here’s the current evidence-based medical recommendation on cold therapy for acute musculo-skeletal injuries per UpToDate.com, the medical website:
“Cold therapy is commonly used during the inflammatory and early reparative phase (ie, up to seven days after injury) to decrease swelling and pain. The benefits of cold therapy have been demonstrated with magnetic resonance imaging of the perfusion of muscle tissue and diffusion of water molecules following cryotherapy wherein tissue temperature and perfusion were both noted to be significantly reduced. Cryotherapy has been demonstrated to have effects on acute injury including decreased pain, decreased swelling, and increased range of motion. However, the early observational studies demonstrating the benefit of cryotherapy in patients with ankle sprain were of limited methodological rigor and it remains unclear if cryotherapy improves functional outcomes significantly.”
Do with that what you will, and don’t overdo the cold therapy. 15 minutes on and 45 minutes off is the standard recommendation; don’t freeze the tissue, and excessive cooling can damage nerves.
For foot pain (gout, flexor tendonitis, plantar fasciitis, I’ve had them all) I use ice initially. At some point I’ll switch to heat (hot water soaks). For me the relief I experience dictates whether I use hot or cold.