In Sketching Men, veteran art instructor Koichi Hagawa, PhD explains how to quickly capture the dynamic male form through two distinct styles of sketching:

Very rapid (1-3 minute) line drawings that capture the essence of the subject's posture and movement-perfect for recording athletic action poses in the moment
More finished tonal drawings, which take a bit longer to render (7-10 minutes), but fill in lots of interesting texture and wonderfully realistic details and nuances, including the play of light and shadow, three-dimensional form and a sense of mass and balance

Learn to sketch the following:

Individual body parts and their bones and muscles
Objects held in the hands and with both arms
Standing and sitting poses
Transitions from prone and sitting poses to a standing pose
Bending, reaching and leaning poses
Pushing, throwing and dancing poses
Folds, gathers and drape of clothing

This book contains hundreds of detailed studies and helpful examples. Your sketches will improve rapidly as you learn all about how human anatomy-the skeleton, muscles and posture-all come together to express the uniquely male form. When you hone your line and tonal drawing skills with this book, all of your artwork will improve as a result, no matter the application: storyboarding, cartooning and graphic novels, illustration, formal drawings, painting and more!