Now tightly close your fist. While watching the second hand of the timer, count the number of times you can open and close your fist in 30 seconds. Open your hand fully so that your fingers are stretched out as far as possible, then make a fist as fast as you can. Make as many fists as you can in 30 seconds. Record the number of times you opened and closed your fist during the 30-second interval.
Half fill the pail with water and ice.
Be sure you use sufficient ice, enough to last for five minutes without melting completely. Wait two or three minutes, allowing the water temperature to reach 10 to 15 degrees Celsius. Record the temperature in the data table. Grip the folded sponge in the same hand as before. Immerse your closed fist, up to the wrists, in the ice water.