Celebrity Trainer 'Ray' Grayson Visits KCAL9Grayson practices HIIT, or high-intensity interval training, to build muscle and burn fat.
Lorri Ann Codes' Tips For High Intensity Interval TrainingWant a workout that is simple, effective and doesn’t cost money? Try High Intensity Interval Training!

More From CBS Los Angeles

Play.It
Introducing Your New Podcast Network

Listen Live