Experimental Protocol of a Three-minute, All-out Arm Crank Exercise Test in Spinal-cord Injured and Able-bodied Individuals

The overall goal of this protocol is to objectively measure the arm strength of spinal injury patients, using a three-minute exercise. This method can help answer key questions in the sports science field, such as the influence of dietary supplments on exercise performance. The main advantage of this test is that it is applicable for able-bodied as well as spinal cord injured athletes.

First, turn on the arm crank ergometer. Then open the associated software. In the software control, select a three-minute, all-out ergometer test.

Based on the participant's mass, set the relative torque factor to 0.2. For example, a 100-kilogram participant would require 20 Newton-meters of torque. The torque factor for a quadriplegic participant however, is based on the lesion.

Next adjust the height of the arm crank to the shoulder joint of the participant and take note of the setting. The height is measure from the floor to the fixation of the crank. Next, set the chair.

Able-bodied participants can use the provided chair. Set the chair's position and record the distance between the wall fixation and the chair. For wheelchair-bound participants, use the fixation set to secure their wheelchair relative to the arm crank.

Then take note of the distance between the chair and the wall. Wheelchair-bound participants also need to have their upper-body secured and if needed, secure their hands to the peddles using wrist bands. To analyze whole blood lactate concentration, first calibrate the blood analyzer, using a 12 millimolar standard.

Then disinfect the participant's earlobe and take the first blood sample using a capillary. Release the blood into a commercial hemolysis cup and shake it into the solution. Then place the cup into the first sample position of the lactate analyzer.

To monitor the participant's heart rate, secure the heart rate belt around the participant's chest. And fix the monitor to the arm crank ergometer. Using the monitor's controls, collect the data.

To collect oxygen consumption data, calibrate the system just before the test with the mask off. From the software control, start the volume calibration and store the results when the error is below 3%Then using the calibration gas, continue the automatic gas calibration. When 8 green lights are displayed, the calibration is complete and the process was successful.

Store the results and then securely close the calibration gas bottle. Next, remove the spirometer from the gas mask to calibrate it in the room air. Then start the software-controlled calibration for the spirometer.

Now reattach the spirometer to the gas mask and but the mask on the participant. Then, secure the hose to the participant so it does not interfere with the movement of the crank. Oxygen consumption can now be measured.

Start the baseline measurements one minute before beginning the test. Then start the test with a two-minute warmup. During the last 30 seconds of the warmup, maintain the cadence at 60 RPM, then countdown the last 10 seconds to the start of the all out test phase.

Now have the participant accelerate the arm crank ergometer as fast as possible and try to maintain this cadence for a full three minutes. To maintain standards, do not encourage the participants but do alert them of every 30-second interval. After three minutes, start the cool down phase.

And immediately take a blood sample by capillary from the ear lobe for the lactate measurements. Continue taking blood samples on two-minute intervals over the next 10 minutes. After three minutes of cool down, stop measuring oxygen consumption and remove the mask.

Once all the blood samples are collected, process them concurrently using the lactate analyzer. The test to retest reliability of the described exercise was investigated using 21 recreational trained, non-smoking individuals. Apart from time-to-peak, which depended on the participant's reaction time, the other parameters were moderately consistent between the two tests.

Based on the peak-power comparison between tests, and a Bland-Altman plot of the data, the three-minute all-out arm crank test was reliable in able-bodied participants. In a 2nd experiment, the test was performed on 17 able-bodied participants, 10 paraplegic participants, and seven tetraplegic participants with complete lesions between C5 and C7.Overall, the able-bodied and paraplegic participants showed very similar results for maximal and mean power whereas the tetraplegic participants performed with a significantly lower power output. After watching this video, you should have a good understanding of how to perform a three-minute all-out test at the arm crank ergometer.

Once mastered, this technique can be done in 45 minutes if it's performed properly. While attempting this procedure, it's important to remember to perform a familiarization trial beforehand and to calibrate all the devices used during the test procedure.