Cardio can have both positive and negative effects on muscle growth, depending on various factors. It's important to note that cardio does not directly send a muscle-building signal like resistance training does. However, there are scenarios where cardio can benefit muscle growth. For example, if someone has poor cardiovascular stamina and endurance, incorporating a moderate amount of cardio can improve their cardiovascular capacity, allowing them to work out harder during weight training sessions.
Additionally, certain forms of cardio, such as sprinting or high-intensity interval training (HIIT), can be more muscle-preserving and even muscle-building. These types of cardio exercises engage fast-twitch muscle fibers and can contribute to muscle growth. On the other hand, long-duration, steady-state cardio may have a greater potential to interfere with muscle growth, especially if someone is already struggling to consume enough calories to support muscle growth.
Context is crucial when considering the impact of cardio on muscle growth. Factors like individual goals, nutrition, and overall health should be taken into account