James Jackson

James Jackson is a personal trainer who uses his expertise in strength and conditioning to create helpful workout tutorials that show fitness enthusiasts how to build muscle while staying safe in the gym. He draws on the latest sports science data as well as tried and tested training techniques to get the best results for his clients without them having to live in the gym.

Find out the average height for 17 year old males and females in feet.

Find out the average buttocks size for men and women and learn how to measure your glutes.

Learn what the science has to say about the average arm size in males and females.

Discover how to grow taller naturally and achieve your full height potential.

Learn why a normal waist size isn’t necessarily a healthy waist size.

Discover the average height for men in America and in the world.

Find out how much 4 year old boys and girls should weigh and learn how tall they are on average.

Learn the average height for a 12 year old boy and a 12 year old girl.

How tall should an 11 year old be in feet? Learn the precise, data-backed answer and more.

Find out the average height for 14 year olds in the USA.