Isometric exercise is undergoing somewhat of a renaissance recently and is increasingly being incorporated into physical fitness and athletic training.
Isometric exercise is an unconventional exercise type that requires holding a static position without any movement or motion. It is known as static strength training and is different from other popular exercise methods such as regular weight training or plyometrics.
It was a popular method of training in the 1960s. At the height of the Cold War, both American and Soviet weight lifters were incorporating this style of training into their workout routines.
Bob Hoffman, the founder of York Barbell company, actually made an isometric power rack. The trainer would stand in the rack and push a weighted barbell against two sets of pins.
The amateur wrestler, Henry Wittenberg, attributed much of his success to the practice of isometrics. From 1940 to 1952, he remained undefeated in over 400 consecutive matches and won a gold medal at the 1948 Olympics.
Bruce Lee, an outstanding athlete, was also a big fan of isometrics and you can see him engaged in an isometric exercise in the photograph below.
However, like all exercise trends, the popularity of isometrics gradually faded away to be replaced by the latest “new” idea.
Understanding Isometric Exercise
The Science Behind Isometric Exercise
Isometric exercise engages the muscular system by generating tension in muscles, without any accompanying movement. It triggers the recruitment of motor units, the basic functional units of muscle tissue.
As the tension in the muscle increases, more motor units are activated, leading to greater force production. This process is called high-threshold motor unit recruitment and is the foundation of isometric exercise.
It trains the neuro-muscular system to become better coordinated so that increased force can be generated.
One limitation is that this increase in force is only at the angle that the muscle and joint has been trained in. Let’s take a simple example. Say you have a length of thick rope and, whilst standing you loop the middle under one foot. You then grab each end with each hand and position your arms so your elbow is at a right angle. With the rope taut you then try to perform a curl. Your hands won’t actually move but you’ll feel you biceps contract. You should hold the position with as much effort to cause your arms and upper body to tremble at the effort.
This is an amazing bicep workout and will cause hypertrophy as well as strength gains. However, those strength gains will be mainly at the point at which your arms are at a ninety degree angle.
This limitation is easily resolved by training isometrically at a number of different angles, as shown in this study.
This is exactly how Louie Simmons trained his trainees at his gym – Westside Barbell.
To train the deadlift, a barbell would be loaded with a weight that the lifter would be unable to lift from the floor. The lifter would attempt to pull the barbell up for 3 to 6 seconds at a time; this would be repeated six times.
The barbell would be raised on six inch boxes and again the lifter would try to deadlift the barbell using the same set/rep routine.
The barbell would be raised to knee hit and the process continued. Two further levels were used: two inches above knee height and just short of lock out.
In this way all the neuro-muscular angles involved in the deadlift were trained.
Of course, Louie utilised other training methods but the point is he recognised the contribution isometrics could make to strength development.
Differentiating Isometric Exercise from Other Types of Exercise
Isometric exercise differs from other more dynamic exercises, such as running or regular weight training which involve movement and changes in muscle length.
The Advantages of Isometric Exercise for Athletes
Isometric exercise can help athletes to increase their strength and endurance, leading to enhanced athletic performance.
This exercise method enables athletes to target specific muscles or muscle groups effectively, leading to improved muscle activation and recruitment. It helps to coordinate the neuro-muscular connection enabling greater force generation.
Isometric exercises are also useful in injury prevention, as they help to improve muscle strength and stability around joints, leading to a reduced risk of injury.
Additionally, isometric exercise can help to improve overall body control and stability, leading to better balance and coordination, which are essential for athletic performance.
Varieties of Isometric Exercises
Static Isometric Exercises
Static isometric exercises involve holding a muscle in a contracted position for a specific duration without any movement. This type of exercise is useful for improving muscle strength and endurance. Examples of static isometric exercises include planks, wall sits, and the bridge pose.
Isometric Exercises with Equipment
Isometric exercises can also be performed with equipment such as resistance bands, exercise balls, and weight machines. Using equipment can increase the intensity of the exercise and provides more resistance.
I’ve outlined above how isometrics can be used when training to perform the deadlift. Similar methods can be used to train in the barbell squat and bench press.
In both these cases, instead of trying to lift an immovable barbell you would perform the exercise in a squat rack and would push the barbell against the fixed safety pins for 3 to 6 seconds at a time for six sets.
For instance, you could set the pins up so that the barbell pushed against them when in a squat position with your legs at a right degree angle. You would then perform the required number of reps/sets before raising the pins slightly and repeating the process.
The pins could be raised a number of times with the last being when the legs were just short of full lock out.
Isometric Exercise and Performance in Sports
Benefits of Isometric Exercise for Strength and Endurance Improvement
Isometric exercise can improve muscle strength and endurance by creating tension in the muscles and stimulating muscle fiber recruitment. Athletes who include isometric exercise in their training regimen may experience improved performance in their respective sports.
One study gave the following advice:
“To increase muscle hypertrophy, IST (isometric strength training) should be performed at 70-75% of maximum voluntary contraction (MVC) with sustained contraction of 3-30 s per repetition, and total contraction duration of>80-150 s per session for>36 sessions. To increase maximum strength, IST should be performed at 80-100% MVC with sustained contraction of 1-5 s, and total contraction time of 30-90 s per session, while adopting multiple joint angles or targeted joint angle.”
So, this would be longer contractions at lower intensity for hypertrophy and shorter contractions at higher intensity for a focus on strength gains.
Joint angle can also determine the degree of hypertrophy. This study showed that isometric training at longer muscle lengths produced greater muscular hypertrophy when compared to equal volumes of shorter muscle length training. Additionally, long muscle length training results in greater transference to athletic performance. For example, training the bicep with the arm outstretched would result in greater hypertrophy than when the arm is in the fully bent or flexed position.
Isometric Exercise and Injury Prevention
Isometric exercise can also play a role in injury prevention by improving joint stability and reducing the risk of injury. When performed correctly, isometric exercise can activate the muscles that support the joints, thus improving joint stability and reducing the risk of injury. Additionally, isometric exercise can be a valuable tool in the rehabilitation of injured athletes.
Specific Applications of Isometric Exercise in Different Sports
Isometric exercise can be used to improve performance in various sports.
For example, basketball players can benefit from isometric exercises that focus on the legs and core muscles to improve jumping ability and body control.
Football players can use isometric exercises to improve overall strength and prevent injuries.
Gymnasts can use isometric exercises to improve body control and stability. What is the ‘iron cross’ hold if not an isometric.
Tennis players can use isometric exercises to improve grip strength and stability during swings.
Each sport has unique demands, and isometric exercise can be tailored to meet those demands and improve overall performance.
Integrating Isometric Exercise into Athletic Training
Designing an Isometric Exercise Program
To design an effective isometric exercise program for athletes, coaches and trainers should consider the specific sport and the athlete’s individual needs and goals. The program should include a variety of isometric exercises that target the major muscle groups used in the sport. The exercises should be progressively challenging, and the program should be adjusted regularly to prevent plateaus and accommodate the athlete’s changing needs.
Determining Frequency, Duration, and Intensity
The frequency, duration, and intensity of an isometric exercise program will vary depending on the athlete’s training goals, level of fitness, and sport-specific needs. Generally, isometric exercises should be performed 2-3 times per week, with each session lasting 20-30 minutes. The intensity of the exercises should be gradually increased over time, with a focus on maintaining proper form and technique.
Frequently Asked Questions
Can isometric exercise replace traditional weightlifting?
Isometric exercise can be a useful addition to a weightlifting program, but it cannot replace traditional weightlifting entirely. Isometric exercise primarily targets strength gains at specific joint angles, while weightlifting can target a wider range of muscle groups and improve overall muscle mass and power. Incorporating isometric exercises as part of a comprehensive training program can lead to improved athletic performance and injury prevention.
How often should athletes incorporate isometric exercise into their training?
The frequency of isometric exercise depends on the athlete’s goals and overall training program. It is generally recommended that athletes incorporate isometric exercises 2-3 times per week, with each session lasting 10-20 minutes. The duration and intensity of the exercises should be gradually increased over time as the athlete becomes more comfortable with the exercises and gains strength. It is important to consult with a qualified trainer or healthcare professional to design an isometric exercise program that is appropriate for the athlete’s needs and fitness level.