This is an excerpt from NSCA's Guide to Program Design eBook by NSCA -National Strength & Conditioning Association & Jay Hoffman.
Biomechanical Analysis in Practice
For the purpose of understanding the movement being analyzed, strength and conditioning professionals should use the following four questions. First, what are the patterns of movement (i.e., concentric, eccentric, or isometric), and in which planes do they take place? Second, what joints are involved during the activity? Third, what muscles are recruited, and what are the muscle actions? Finally, what is the duration of time that the athlete will be actively engaged in the athletic event? With these key questions, strength and conditioning professionals can determine the demands placed on the body during the sport (6, 33, 34). The ultimate goal of analysis is to manipulate and match the acute variables that govern the program's design to match the metabolism and movements involved in the sport.
Typically, biomechanical evaluations require strength and conditioning professionals to analyze videos of athletes performing their sports. Those without access to advanced video equipment can accomplish this type of analysis by watching simple video of athletes during practices or games. The following are some very basic procedures for video analysis that strength and conditioning professionals can follow (9).
- View a video of an athletic performance or activity.
- Select a specific movement in the sport (e.g., a jump shot in basketball or a takedown in wrestling). To completely analyze the sport, several movements or skills may need to be examined. Look at the entire sequence of competition to get a feel for the demands of the sport.
- Identify the joints around which the most intense muscular actions occur. Running and jumping, for example, involve intense muscle actions at the knee, hip, and ankle. Intense exertion doesn't necessarily involve movement. Considerable isometric force may have to be applied to keep a joint from flexing or extending under external stress.
- Determine whether the movement is concentric, isometric, or eccentric.
- For each joint identified above, determine the range of angular motion. Observe how the joint angle changes throughout the movement and which plane it occurs in.
- Try to determine where the most intense effort occurs within the range of motion around each particular joint. Sometimes facial grimaces or tense muscles seen on video can help identify points of peak intensity.
- Estimate the velocity of movement in the early, middle, and late phases in the range of motion. If using video, determine the time between frames to examine the movement over the time of the activity.
- Select exercises to match the limb's ranges of motion and angular velocities, making sure that the exercises are appropriately concentric, isometric, or eccentric.
Through this type of biomechanical analysis, strength and conditioning professionals can make sure that training programs reflect these demands (see table 1.2).
It is important to remember that although analyzing sporting movements and matching the proper exercises in the weight room are vital to the sport-specific nature of resistance training programs, many exercises might be considered universal in that all athletes need them. These exercises include squats, pulling motions (e.g., hang cleans), and presses, such as the bench press. Such exercises provide the core around which a program is built. Integration of whole-body, multijoint exercise movements is vital because single-joint exercises alone cannot improve neurological coordination between joints.
Read more from NSCA's Guide to Program Design by National Strength and Conditioning Association.