From Muscle Contractions to Life-Saving Innovations: My Journey at the Stevens Pre-College Program in Biomedical Engineering

Over the summer, I discovered the electrifying world of biomedical engineering, where I explored muscle contractions, coactivation, and neuromuscular electrical stimulation.

BLOGNEUROLOGY

7/21/20233 min read

a person holding a robotic hand in front of a mirror
a person holding a robotic hand in front of a mirror

My unforgettable journey at Stevens' Pre-College Program was nothing short of extraordinary. It's a chapter in my life that I am grateful for, thanks to the incredible scholarship from Stevens Institute of Technology that not only opened doors to the captivating world of biomedical exploration but also introduced me to a circle of remarkable new friends. During this transformative experience, we delved into a multitude of experiments, from recording heartbeats with precision to scrutinizing foot scans on a wobble board, uncovering the intricacies of proprioceptors. Yet, amidst this scientific tapestry, it was the electrifying electromyogram experiment that was the most fascinating.

The electromyogram lab consisted of 4 parts: (i) assessing how concentric and eccentric muscle contractions activate your biceps and triceps; (ii) when coactivation occurs; (iii) how increasing loads affect the EMG reading; and (iv) how using an electrical stimulation on your median nerve can allow your body to bypass the typical pathway and go straight to activating your muscles.

We started off by doing a slow concentric muscle movement, like pulling the patient’s arm towards their body, which shortened the bicep muscle and showed activation on the EMG. Then we pushed their arm away from their body, creating an activation of the triceps. In our data in Figure 1, the green spike represents the bicep activation and the purple spike represents tricep activation.

For the next part of our lab, we tested the coactivation of our biceps and triceps by having a much quicker switch from concentric to eccentric muscle contractions. Coactivation occurs when both your bicep and tricep are activated at the same time to provide protection to your joints. See Figure 2

Next, we gradually increased the load of our patient’s muscle contracts to test the muscular response to an increased stimulation. As we increased the pressure on the patient’s forearm as she tried to do a concentric movement, the EMG showed a higher voltage amplitude, meaning that more muscles were being activated. See Figure 3

Lastly, we placed an electrical impulse device on the median nerve, which is near your wrist, and saw that it activated the abductor pollicis brevis muscle resulting in thumb movements. Neuromuscular electrical stimulation (NMES) sends an electrical impulse to your nerve which activates the motor neuron instead of the muscle fiber creating an involuntary muscle contraction. NMES is used to enhance muscle activation, often to retrain your muscles after a neurological injury, spinal injury, cerebral palsy, and many more conditions. I was particularly fascinated by the simplicity of the experiment and its broad impact in medicine, which made me appreciate that not all research experiments need to be complex to be effective.

Overall, during my time at Stevens, I experienced a glimpse of what life would be as a biomedical engineering major and learned much more beyond the signaling in muscle contractions; I learned the importance of biomedical engineering to our society and saw how it could help patients suffering from chronic conditions. Lastly, I saw the importance of my peers, professors, and counselors in making this experience as impactful as it was to me, and hope that it will propel me through my future aspirations.

Figure 1

Figure 2

Figure 3