I am not a doctor but I have been in physical therapy for a total knee replacement. The advice given to me was: use an ice pack for swelling and a heat pad for aching muscles. I was also told how to make a home-made ice pack: In a one-gallon freezer bag mix 1 cup of alcohol with 3 cups of water. This will make an icy/slurpee-type solution that will not freeze solid but remain pliable so you can shape it as needed.
Always apply a cold pack first for up to 15 minutes. This will draw more blood to the affected area (in order to warm it), thereby bringing more of the necessary nutrients for healing.
Heat for tired cold for swollen heat or cold for sore, let your gut tell you on that one.
A cold compress is good for swollen tissues. For tired muscles the best thing is heat or massage.
They constrict, cramp, & spasm in an attempt to prevent losing body heat.
Shivering is the first signs because your muscles are contracting and expanding to make heat, because the more your muscles move the warmer your body temperature will be.
You always ice muscle, tendon, and ligament damage to prevent swelling and further potential damage. It used to be that after the first day or two after an injury, you would apply heat to bring healing blood circulation to the area. It has been found in the past couple of years that ice is somewhat better at bringing healing blood to the damaged area. Either heat or cold will be OK to apply after the first day or two after the injury.
Usually cold, you can get creams for it, but you can also alternate between the two
first aid for heat & cold wave
Do not apply moist heat or vigorously rub the muscles. Rest and replenishing electrolytes should resolve the problem. However, if heat cramps do not improve within 1 to 2 hours, call your doctor or visit an ER.
Use ice for injuries to calm down any damaged tissues that are inflamed or swollen. Use heat for sore muscles, chronic pain and stress.
The hair works as insulation for heat against the cold winds. When it is cold the erector muscles connected to the hair contracts.
If the swelling is due to trauma such as a punch to the jaw, ice is best. If swelling is inside the mouth, an abscess is the most likely cause and heat is best as it draws the pus to the surface where it will burst and the relief will be instant.
If you mean what comes first in the year, than cold.