Coaches and athletes alike are well aware that the way a practice is structured has an effect on how well motor skills are learned.  A distinction can be made between blocked and random practice.  Blocked practice involves working on a specific skill over and over again.  This has been found to be more beneficial for athletes still in the early stages of learning a skill, and can result in an increased performance of that skill during that practice session.  Conversely, random practice involves practicing several skills in a random order.  This results in better retention (learning) of the skill and an increased ability to transfer that learning to another context.

As you can see, each type of practice can benefit the athlete depending on their skill level and the nature of the sport in which these skills will be applied.  Tennis provides a perfect context to use to describe how a coach can use both blocked and random practice to help their players.  Before a player has learned the basics of a forehand groundstroke in tennis, blocked practice will give them the repetition that they will need to learn the basic mechanics behind the stroke.  However, a player who only practices the forehand repetitively will be in trouble when they get into a match and their opponent hits it somewhere else.  In this case, a focus on random practice will prepare them better for the uncertain nature of the game of tennis.  Based on the relative benefits of each type of practice I believe that random practice is more worthwhile, mainly because it involves training one’s body to prepare for the unexpected.  Regardless of the sport or context, an athlete who is more prepared to deal with whatever situation arises will be more confident and perform better.