Having pain or discomfort with lunging can greatly affect your workout! In this snip bit, we are going to discuss ways we can alter our body to continue exercising and avoid that nagging knee pain with exercising!
The lunge exercise is a popular lower body movement that targets the muscles of the hips, thighs, and glutes. It is a unilateral exercise that requires an individual to step forward with one foot and lower the body to the ground, while keeping the other foot stationary. The position of the trunk and lower limb during the lunge exercise can have a significant impact on the joint moments experienced by the lower extremity joints of the lead limb.
Studies have shown that the position of the trunk has a significant impact on the lower extremity joint moments of the lead limb during the lunge exercise. This is because the head, arms, and trunk make up approximately 55% of the body mass. Therefore, the position of the trunk can significantly alter the distribution of forces within the body during the lunge exercise. A forward lean at the trunk has been reported to substantially increase the ankle plantar flexor moment, hip extensor moment, and activation of gluteus maximus and biceps femoris muscles relative to a vertical trunk posture.
The ankle plantar flexor moment refers to the moment that is experienced by the muscles that plantar flex the ankle joint. The hip extensor moment, on the other hand, refers to the moment that is shared by the muscles that extend the hip joint. The activation of the gluteus maximus and biceps femoris muscles is also increased during a forward-leaning lunge relative to a vertical trunk posture. These muscles are responsible for hip extension, an essential component of the lunge exercise.
Furthermore, the position of the trunk and shank can also have a significant impact on the patellofemoral joint loading of both limbs during the forward lunge. The patellofemoral joint is located between the patella (kneecap) and the femur (thigh bone), and it is responsible for transmitting forces from the quadriceps muscles to the lower leg bones. This joint is particularly vulnerable to stress and can become painful if subjected to excessive loading.
North 40 Physical Therapy Lunge Variation to Avoid Knee Pain
In general, the trailing limb tends to experience greater total joint stress during the lunge exercise. However, limiting the forward translation of the lead-limb shank may reduce patellofemoral joint stress, but it may come at the expense of increased stress in the trailing limb.
Research also suggests that the forward-leaning lunge can produce more significant patellofemoral joint loading variables compared to the backward-leaning lunge. This is because the joint farthest away from the load will receive a majority of the stress. Therefore, in an upright lunge, the forward knee will experience more torque as it is the joint farthest from the load of the body. This places more responsibility on the knee extensors, making it a more quadriceps-dominant movement.
However, by slightly leaning the upper body weight over the mid-thigh during a forward-leaning lunge, the demand will be evenly distributed across the hip, knee, and ankle. This means that the muscles moving those joints through extension will both bear responsibility in the exercise. As a result, a slight forward lean can increase glute involvement, making it a more balanced exercise for the lower body.
In conclusion, the position of the trunk and lower limb during the lunge exercise can have a significant impact on the joint moments and loading experienced by the lower extremity joints of the lead and trail limbs. A forward lean at the trunk can significantly increase the ankle plantar flexor moment, hip extensor moment, and activation of gluteus maximus and biceps femoris muscles relative to a vertical trunk posture. However, a slight forward lean can also increase glute involvement, making it a more balanced exercise for the lower body. Therefore, it is important to consider the position of the trunk and lower limb during the lunge exercise to optimize the training effect and minimize the risk of injury.
