Pectorals
What are they?
The pecs are a group of muscles situated at the chest. The pectoralis major is a thick, fan-shaped muscle making up the bulk of the chest muscles. It has fibres attaching along the collarbone (the upper pecs or clavicle head portion) and along the front of the sternum, also connecting to the ribs and abdominal muscles, the upper arm and front of the shoulder.
How do they work?
During cycling both the pec major and minor stabilise the shoulder blade and help support the shoulder girdle when your hands are on the handlebar. The pec minor stabilises the shoulder blade by drawing it forward and down against the thoracic wall, and assists with rib elevation during breathing. The pecs’ activation increases as your cycling intensifies. They’re also heavily involved in ‘locking’ your arms in when in a very flexed, aero position.
What goes wrong?
Due to the prolonged flexed position of cycling these muscles are prone to tightness, causing increased flexion of the mid to upper spine and pulling shoulders forward, increasing the risk of injury. Weak pecs reduce your ability to stabilise the upper body. This has the potential to cause injury because other areas of your body, such as the lower back, try to compensate for the weakness.
How to fix it
Regular stretching release techniques are recommended to help maintain good posture and flexibility. This can be as easy as stretching on a doorway, opening the chest up and bringing the upper body out of a flexed position. Push-up holds and front planks are great stability moves. Due to the pecs’ origins they are important muscles to strengthen after a fractured collarbone because they help stabilise and support this area.