Boosting Your Heart Rate
Ankle weights do increase cardio intensity, according to a study in the June 1988 edition of "Medicine and Science in Sports and Exercise." Cedric X. Bryant, chief science officer for the American Council on Exercise, summarizes the results of research by claiming ankle weights ranging from 1 to 3 pounds can increase heart rate by an average of three to five beats per minute and oxygen uptake by five to 10 percent. While that's a measurable aerobic benefit, Bryant points out ankle weights prove less effective than hand or wrist weights during cardio activity.
Overloading Your Joints
However, ankle weights can cause excessive joint and muscle strain during aerobic training. They could alter your biomechanics, explains Bryant. Kent Adams, director of the exercise physiology lab at Cal State Monterey Bay, further explains that extra weight around your ankles increases the impact load on your lower-body joints. That extra load can lead to serious overuse and repetitive stress injuries, according to Len Kravitz and his colleagues at the University of New Mexico. For a bigger cardio boost, Bryant and Kravitz suggest wearing a weighted vest. Adams suggests picking up the pace or adding hills to your walking route.