NASM Group Fitness Instructor Practice Exam 2026 – Complete Preparation Guide

Individuals affected by the hormone relaxin, which is produced during pregnancy, experience increased joint laxity and flexibility. Relaxin helps prepare the body for childbirth by relaxing the pelvic ligaments and joints. While this increased flexibility can be beneficial, it also makes the joints more susceptible to injury, particularly during high-impact or dynamic movements.

Plyometric exercises involve explosive movements that place a significant amount of stress on the joints, such as jumping and bounding activities. Because these exercises require rapid changes in direction and load, they can increase the risk of joint strain and instability for individuals with heightened laxity due to relaxin. For this reason, it is advised that those affected by relaxin avoid plyometric exercises to protect their joints from potential injuries.

In contrast, other forms of exercise, such as cardio, isometric, and strength training, can be done with modifications to ensure safety and stability, making them generally more suitable choices.