Meet 75-year-old bodybuilder-grandma Ernestine Sheperd. She started exercising at the age of 56. Now she starts her day with a 10-mile (16 km) cross. Meet 75-year-old bodybuilder-grandma Ernestine Sheperd. She started exercising at the age of 56. Now she starts her day with a 10-mile (16 km) cross.