Mathew Knowles, also known as Beyonce’s former manager (and father), used to make Beyonce run three miles while singing the entirety of her album. She allegedly did this regime seven days a week, demonstrating an intense commitment to her craft through physical dedication. Beyonce’s relentless training gave her a unique strength as a performer; her ability to execute intense choreography during her concerts without sounding winded or tired.
Now I am by no means advocating for running three miles a day while belting as intensely as you can - everything in life should be done in moderation, and you should never push yourself to the point of injury (especially where your voice is concerned!). However, adding any sort of cardio to your weekly routine can help to make a night and day difference in your abilities as a performer. As a singer you are the instrument, and thus overall health is incredibly important to the quality of performance you are able to produce, and aerobic exercise lowers blood pressure, decreases risk for heart disease, and immediately improves mood. For singers, there is the added benefit of aerobic exercise like jogging, swimming, or walking improving your breath control. Good, healthy breath support and lung capacity are the foundations of singing, thus at least a moderate level of aerobic fitness is crucial to being a successful singer.
For Broadway, this principle is dialed up to eleven. Not only are Broadway performers expected to be the best technical singers, they are often expected to execute difficult choreography at the same time. This makes cardiovascular fitness inseparable from success as a Broadway performer. Normal people experience difficulty speaking when intensely exercising, i.e. when their heat rate is at roughly ~90% of their maximum capacity heart rate. However, many Broadway shows require their actors, such as Major Attaway in his role as the Genie in Disney’s “Aladdin,” to be full out belting while performing a dance that gets them to over 90% of their maximum heart rate! In fact, the level of physical exertion for a role like the Genie during musical numbers is more than that of even a marathon runner, who usually run at about 70% of their maximum heart rate.
In summary, if you have dreams of being a professional singer, it is in your best interest to do some sort of aerobic exercise. Even just walking for a few minutes a day will dramatically improve your vocal control and your overall health!