AFAA Personal Trainer Certification 2026 – 400 Free Practice Questions to Pass the Exam

The quadriceps group, commonly known as the quadriceps femoris, is a muscle group located at the front of the thigh and comprises four distinct muscles. These muscles include the rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius.

The rectus femoris is unique as it crosses both the hip and knee joints, allowing it to contribute to hip flexion as well as knee extension. The vastus muscles primarily function to extend the knee and are crucial for activities such as walking, running, and jumping. Understanding the composition of the quadriceps is vital for personal trainers, as these muscles play a significant role in lower body strength and stability.

This knowledge helps in designing effective training programs that enhance performance and reduce injury risk in clients engaged in activities requiring lower body strength.