Cryotherapy on Subjective Sleep Quality, Muscle, and Inflammatory Response in Chinese Middle- and Long-Distance Runners After Muscle Damage

Qu, C, Wu, Z, Xu, M, Lorenzo, S, Dong, Y, Wang, Z, Qin, F, and Zhao, J. Cryotherapy on subjective sleep quality, muscle, and inflammatory response in Chinese middle- and long-distance runners after muscle damage. J Strength Cond Res 36(10): 2883-2890, 2022-The purpose of this investigation was to explore the effects of cold-water immersion (CWI), contrast-water therapy (CWT), and whole-body cryotherapy (CRY) on subjective sleep quality, muscle damage markers, and inflammatory markers in middle- and long-distance runners after muscle damage. Twelve male runners from Beijing Sport University completed a muscle damage exercise protocol and were treated with different recovery methods (CWI, CWT, CRY, or control [CON]) immediately after exercise and at 24-, 48-, and 72-h postexercise. The Pittsburgh Sleep Quality Index questionnaire score, lactate dehydrogenase (LDH) activity, myoglobin (Mb) activity, interleukin-6 (IL-6) activity, and soluble intercellular adhesion molecule-1 (sICAM-1) activity were measured at 7 time points (preexercise; immediately postexercise; and at 1-, 24-, 48-, 72-, and 96-h postexercise). Pittsburgh Sleep Quality Index scores indicated that the CRY condition had improved sleep quality compared with the CON and CWI conditions (p < 0.05). In terms of LDH activity, the CRY and CWT conditions had improved recovery compared with the CON and CWI conditions (p < 0.05). In terms of Mb activity, the CRY condition exhibited improved recovery compared with that of the CON and CWI conditions (p < 0.05), and the CWT condition showed better recovery than that of the CON condition (p < 0.05). In terms of IL-6 activity, the CRY condition showed improved recovery compared with the CWI condition (p < 0.05). Finally, in terms of sICAM-1 activity, the CRY condition had enhanced recovery compared with the other 3 conditions (p < 0.05). The results from this study suggest that CRY improves subjective sleep quality and reduces muscle damage and inflammatory responses in middle- and long-distance runners. In addition, CWT reduced muscle damage and inflammatory responses, but its effects on the other parameters were inconclusive.