Exercise Dosing for Pain in Healthy Participants

Subjects' cutaneous mechanical sensitivity threshold will be examined using standard monofilaments that apply a force of 0.008g, 0.02g, 0.04g, 0.07g, 0.16g, 0.4g, 0.6g and 1.0g to the forearm and calf. Percent Baseline to 24 hrs post-intervention will then be calculated (100*Value at 24 hours/Value at Baseline). A filament of different weight is applied to the skin to look at the threshold of response.

Subjects' constant heat pain intensity rating will be assessed using a (45 degree Celsius, 3cm x 5cm heating block applied to the forearm and calf for 3 seconds). Following the stimulus, subjects will rate the intensity of the pain associated with the stimulus using a visual analog scale numbered at 0 and 10, where "0" represents "no pain" and "10" represents "the worst pain imaginable" (0=minimum score, 10 maximum score). Percent baseline to 24 hrs post-intervention will then be calculated (100*Value at 24 hours/Value at Baseline).

Subjects' constant heat pain unpleasantness rating will be assessed using a (45 degree Celsius, 3cm x 5cm heating block applied to the forearm and calf for 3 seconds). Following the stimulus, subjects will rate the unpleasantness of the pain associated with the stimulus using a visual analog scale numbered at 0 and 10, where "0" represents "not unpleasant" and "10" represents "the most unpleasant sensation imaginable" (0=minimum score, 10 maximum score). Percent baseline to 24 hrs post-intervention will then be calculated (100*Value at 24 hours/Value at Baseline).

Subjects' radiant heat sensitivity will be assessed using a temperature ramp from 30 degrees Celsius to 50 degrees Celsius over 60 seconds with participant defined cutoff in temperature (degrees Celsius) reading at their "sensitivity threshold" to the thermal stimulus (IITC Thermal Stimulus Apparatus with custom heated glass). This will be assessed on the forearm and calf. Percent baseline to 24 hrs post-intervention will then be calculated (100*Value at 24 hours/Value at Baseline).

Subjects' radiant heat pain threshold will be assessed using a temperature ramp from 30 degrees Celsius to 50 degrees Celsius over 20 seconds with participant defined cutoff in temperature (degrees Celsius) reading at their "pain threshold" to the thermal stimulus (IITC Thermal Stimulus Apparatus with custom heated glass). This will be assessed on the forearm and calf. Percent baseline to 24 hrs post-intervention will then be calculated (100*Value at 24 hours/Value at Baseline).

Subjects' pressure pain threshold will be assessed using a pressure algometer (Wagner Instruments; 1cm round probe applied at constant ramping pressure until participant defined cutoff in kg at "pain threshold"). This will be assessed on the forearm and calf. Percent baseline to 24 hrs post-intervention will then be calculated (100*Value at 24 hours/Value at Baseline).

Subjects' constant pressure pain intensity rating will be assessed using a pressure algometer (Wagner Instruments; 1cm round probe applied for 2 seconds at participant defined threshold). Following the stimulus, subjects will rate the intensity of the pain associated with the stimulus using a visual analog scale numbered at 0 and 10, where "0" represents "no pain" and "10" represents "the worst pain imaginable" (0=minimum score, 10 maximum score). This will be assessed on the forearm and calf. Percent baseline to 24 hrs post-intervention will then be calculated (100*Value at 24 hours/Value at Baseline).

Subjects' constant pressure pain unpleasantness rating will be assessed using a pressure algometer (Wagner Instruments; 1cm round probe applied for 2 seconds at participant defined threshold). Following the stimulus, subjects will rate the unpleasantness of the pain associated with the stimulus using a visual analog scale numbered at 0 and 10, where "0" represents "not unpleasant" and "10" represents "the most unpleasant sensation imaginable" (0=minimum score, 10 maximum score).This will be assessed on the forearm and calf. Percent change from baseline to 24 hrs post-intervention will then be calculated (100*Value at 24 hours/Value at Baseline).

Heart rate will be measured before and after each exercise session. Percent pre-exercise session in heart rate (bpm) from start to end of exercise session will be calculated (100*Value at end trial/Value at start of trial).

Subjects will indicate rate of perceived exertion before and after each exercise session. Percent of pre-exercise RPE from start to end of exercise session will be calculated (100* end of trial / start of trial).