Jen Lewis is a fitness instructor based in the United States, who has made it her mission to reach as many people as possible with her love for fitness. Jen’s YouTube channel: Cardio Party Mashup Fitness hosts a great variety of workouts, of all different lengths, including: week-long fitness ...

So have you got a passion for physical fitness that you're thinking about turning into a career? That can be a smart move, especially since fitness instructor jobs are predicted to grow by 39 percent through 2030, according to the Bureau of Labor Statistics. Other fitness-based jobs are likely to ...