This study is a randomized, double-blind, controlled clinical trial with 3 independent groups. One group (control-control or CON-CON) will not exercise and will not have any cryotherapy intervention, a second group (control or CON) will exercise but use a "room temperature" cold-pack, and the cryotherapy group (CRYO) will exercise and receive a cold cold-pack every day for 15-min.
We anticipate to compare means in several markers (functional and in blood) using a two-way analysis of variance (ANOVA, time x condition) where time is before, and 0, 24, 48, 72, 96, and 264 hours after exercise (6 visits) and conditions are CON-CON, CON, and CRYO.
VISIT ONE Before the informed consent process, potential participants will rest for 10 minutes, and their blood pressure will be taken to confirm eligibility. Once eligibility is confirmed, participants will go through the informed consent process. After the participants have signed the informed consent, the participants will be randomly allocated to one of the 3 groups. Then, a blood sample (two 10-ml tubes) from an antecubital vein of the dominant arm will be drawn. After the blood drawn, a set of functional tests ( i.e., arm girth, active range of motion (ROM), peak pressure threshold (PPT), and maximal voluntary isometric contraction (MVIC)) will be performed (the description of each test can be found below). Once the functional tests are performed, participants from the CON-CON group will be dismissed. Participants from the other 2 groups will perform a controlled exercise-induced muscle damage (EIMD) through eccentric exercise (protocol description below). Immediately after the EIMD protocol, participants in the CON group will receive 15-min of a room temperature cold-pack in room RSC 100. Participants in the CRYO group will receive 15-min of a cold cold-pack in room RSC 100. Treatment will be performed by RAs that were not involved in any testing session. After treatment, CON or CRYO, the same set of functional tests will be performed in room RSC 117.
VISIT TWO to FOUR (24, 48, and 72 hours after VISIT 1, respectively) Participants will get a blood draw (two 10-ml tubes) from an antecubital vein of the dominant arm. Then, participants in the CON group will receive 15-min of a room temperature cold-pack in room RSC 100. Participants in the CRYO group will receive 15-min of a cold cold-pack in room RSC 100. Treatment will be performed by RAs that were not involved in any testing session. Participants from the CON-CON group will not have any treatment. Finally, the set of functional tests will be performed.
VISIT FIVE (96 hours after VISIT 1) Participants will get only a blood draw (two 10-ml tubes) from an antecubital vein of the dominant arm. Then, participants in the CON group will receive 15-min of a room temperature cold-pack in room RSC 100. Participants in the CRYO group will receive 15-min of a cold cold-pack in room RSC 100. Treatment will be performed by RAs that were not involved in any testing session. Participants from the CON-CON group will not have any treatment.
VISIT SIX (264 hours after VISIT 1) Participants will get a blood draw (two 10-ml tubes) from an antecubital vein of the dominant arm. Then, the set of functional tests will be performed.
