Change of direction (COD)

Change of direction (COD) is the ability to decelerate, turn the body toward a new direction and accelerate again along a planned path.^{1International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 355.},^{2Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 550.} It has three phases: deceleration through an eccentric contraction, the plant through an isometric contraction, and reacceleration through a concentric contraction.^{1International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 355.} Rounding a base or running a preplanned route with at least one turn are examples.^{1International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 355.}

A turn made in response to a stimulus, such as a defender’s cut, is agility: it requires a rapid decision before the movement.^{1International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 355.}

In practice

• Match training to the cutting angle.^{3Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 549.} The NSCA says shallow cuts under 75 degrees with ground contact under 250 ms respond to training much like speed work.^{3Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 549.} Cuts of 75 degrees or more can take longer than 250 ms because of the braking load, so emphasize eccentric and maximal strength work.^{3Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 549.}
• Coach trunk control during deceleration, then turn the trunk and hips toward the new direction.^{4Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 551.} Keep a low center of mass and avoid stiff-legged braking.^{4Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 551.}
• Choose the test for the movement you want to assess: the 505, modified 505 and L-run have only a moderate relationship with each other and don’t measure the same type of change-of-direction ability.^{2Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 550.}
• Start beginners with 2 to 3 repetitions, lengthy rest and few direction changes, then add variables over time.^{5International Personal Trainer Academy, Certified Personal Trainer Textbook, p. 356.}