Ice baths: The effects of three different immersion times on numbness (sensation of pressure), surface temperature and perceived pain.
Objectives: Determine if numbness differs in magnitude and duration between 10, 15 and 20 minute ice bath immersions, when temperature is held constant.
Design: Dependent variables: sensation of pressure (g), perceived pain (cm), and skin temperature (degrees C). A repeated measures 3 x 19 factorial guided study.
Conditions were 10, 15 and 20 minute ice bath immersions. Measurement times were before immersion, 1, 3, 5, 7, 9, 10, 11, 13, 15, 17, 19 and 20 min immersion and 1.5, 3, 5, 7, 9 and 11 min post-immersion.
Subjects: Eighteen college-aged volunteers.
Measurements: Subjects participated in three ice bath immersions (10, 15 and 20 min). Sensation of pressure was tested over the anterior talofibular ligament prior to immersion and 1.5, 3, 5, 7, 9 and 11 min post-immersion.
Cold induced pain was recorded at baseline (prior to treatment), every two minutes during immersion (beginning with 1 min), immediately following foot removal (10, 15 and 20 min), and directly following each monofilament reading (1.5, 3, 5, 7, 9 and 11 min post-treatment).
Water bath and skin temperature were recorded every min (baseline to 11 min post-immersion). ANOVA's and Tukey-Kramer multiple range tests were used to determine significance.
Results: Water bath temperature was held constant at 1 C. Loss of sensation was greater following 20 min of immersion than 10 min of immersion at all post-immersion measurement times. The greatest loss of sensation was at 1.5 min following the 20 min immersion.
Pain peaked at 1 min immersion and declined sharply until 9 min after immersion. Post-immersion pain was significantly greater following 20 min of immersion than 10 or 15 min of immersion.
Skin temperature did not differ among conditions at baseline or during immersion.
Conclusions: Our research supports clinical recommentdations of 12-20 min initial immersion during cryokinetics. There was on difference in water or skin temperature between groups; therefore, the increased magnitude and duration of numbness following 20 min immersion was due to the increased length of immersion. Prolonged immersion past the point of perceived numbness may be beneficial.
Keywords: numbness, cryokinetics, cold water bath, cryotherapy, rehabilitation
N E Johnson, Department of Exercise Sciences, Brigham Young University 2004.