I had a good question about abdominal muscle activation this week, which, unfortunately, I could not answer because there have not been any published studies regarding the core musculature and softball pitching. That said, I may bring some studies from other sports and see if we can find some answers. I was inspired to bring another muscle activation study by Remaley et al (2015) Surface Electromyography of the Forearm Musculature During the Windmill Softball Pitch. This study measures the surface electromyography (EMG) of 4 forearm muscle: flexor carpi ulnaris (FCU), flexor carpi radialis (FCR), flexor digitorum superficialis (FDS), and pronator teres (PT). Their primary functions:
FCU: Flexes and adducts (ulnar deviation) the wrist.
FCR: Flexes and abducts (radial deviation) the wrist.
FDS: Flexes the proximal interphalangeal (PIP) and metacarpophalangeal (MCP) joints of fingers 2–5; also assists in wrist flexion.
PT: Pronates the forearm (rotates it so the palm faces downward); assists in elbow flexion.
They found:
- FCU exhibited the highest activation levels, reaching nearly 500% of the maximum voluntary isometric contraction (MVIC) during the release phase of the riseball pitch. This suggests that the FCU plays a significant role in stabilizing the elbow against valgus stress during the pitching motion.
- Different pitch types elicited varying levels of muscle activation. Breaking pitches like the curveball and screwball showed higher FCU activation earlier in the pitching motion compared to fastballs and riseballs. The changeup pitch demonstrated a decrease in PT activity between the penultimate and final phases, indicating different muscular demands based on pitch type.
- The findings highlight the importance of forearm muscle strength, particularly the FCU, in protecting the elbow joint during pitching. The study suggests that targeted strengthening of these muscles could be beneficial in reducing the risk of overuse injuries among softball pitchers.
Implications: I think this study is intriguing because motion capture really struggles to measure the finger and wrist movement during the pitch accurately. But these findings show that the rise (using the FCU) may require more ulnar deviation and less pronation. Also, the FCU had greater activation for the rise, screw and curve than the drop and fastball. This is likely because the drop and fastball require more pronation. In fact, the highest activation for the PT and FCR is the drop ball. The rise and screw had very similar activation patterns. This study is worth looking at even if you just look at the graphs. They do an excellent job of illustrating their findings.
People to Follow
Since we are on the topic of muscles, I wanted to share a great account that explains a lot about how muscles work while doing certain movements. Remember, every movement requires a synergy of the muscles throughout the body. Amin Hashemi on Workout_Athletics does a great job with illustrations.
