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It can also tense while lowering a load, or resisting it, such as when lowering the weight in a curl. This type of contraction is known as eccentric and occurs when the muscle tenses while lengthening.A final type of contraction is called an isometric contraction, and it occurs when the muscle tenses while not changing length. Examples of this are poses in body building or pushing against an. Sep 11, 2019 Examples of strength exercises that can be done while seated include leg lifts, bicep curls with a weighted object, and isometric arm exercises. Generally, isometric exercises are a good choice for building muscle strength because they are easy, effective, and require no extra equipment. Download Isometric exercise stock photos. Affordable and search from millions of royalty free images, photos and vectors.
- Isometric Exercise Examples With Pictures And Pictures
- List Of Isometric Exercises
- Isometric Exercise Examples With Pictures
An isometric exercise is a form of exercise involving the static contraction of a muscle without any visible movement in the angle of the joint. The term 'isometric' combines the Greek words 'Isos' (equal) and 'metria' (measuring), meaning that in these exercises the length of the muscle and the angle of the joint do not change, though contraction strength may be varied.[1] This is in contrast to isotonic contractions, in which the contraction strength does not change, though the muscle length and joint angle do.
The three main types of isometric exercise are isometric presses, pulls, and holds. They may be included in a strength training regime in order to improve the body’s ability to apply power from a static position or, in the case of isometric holds, improve the body’s ability to maintain a position for a period of time. Considered as an action, isometric presses are also of fundamental importance to the body’s ability to prepare itself to perform immediately subsequent power movements. Such preparation is also known as isometric preload.
- 1Overcoming and yielding isometrics
Overcoming and yielding isometrics[edit]
An isometric action is one where the observable angle of the joints is maintained. While this definition always applies there are various sub-definitions which exist in order to emphasise how effort is being applied during specific isometric exercises.In a yielding isometric exercise the ambition is to maintain a particular body position; this may also be called maintaining an isometric hold. In an overcoming isometric exercise the ambition is to push or pull against either another part of the self, which pushes or pulls back with equal force, or to move an immovable object. On this basis, an overcoming isometric may additionally be referred to as being an isometric press or an isometric pull.
Unweighted isometrics[edit]
In unweighted isometrics the exerciser uses only themselves for resistance. For example, holding a crouched position, or pressing the palms of the hands against each other. Where by the self presses against itself, this is also referred to as self-resistance or Dynamic Tension training.
Weighted isometrics[edit]
Weighted isometrics involve the additional holding of a weight, and the pressing or pulling of an immovable weight or structure. For example, in a bench press set-up the barbell can be held in a fixed position and neither pushed upwards or allowed to descend. Alternatively, in a mid-thigh pull set-up, a person can attempt to pull a fixed, immovable bar upwards.
Isometrics in combination with dynamic exercise[edit]
Isometric training is seldom used by itself and it is usually incorporated into a wider training regime. For instance, an isometric plank may be incorporated into a plyometrics regime. In addition, when a subject performs a dynamic movement, supportive muscle groups can work isometrically. For example, if a person squats while holding a dumbbell in front of their chest, then their arm action will be relatively isometric, whilst their leg action is dynamic.
In a sporting context, the use of a pure isometric action is rare. In skiing, for example, the skier consistently maintains a crouched position. Whilst this may be considered to be an isometric hold, there is also an amount of dynamic movement as the skier alters how deep the crouch is during their travel. Thus, isometrics can be said to be involved in and supportive of the overall skiing action, even though it is not solely isometric in nature.
In weight training and calisthenics, it is often the case that one phase of the exercise is more difficult to perform than others. If the exerciser tends to fail at this point then it is referred to as a sticking point. An isometric hold may be incorporated to strengthen the exerciser's action at this point. For instance, a sticking point in a heavy back squat is usually the lowest position reached. An isometric hold can be adopted in this position in order to strengthen the lifter's ability to hold the weight there. Over a period of training this can help them to lift the weight more easily from this position and thereby eliminate the sticking point.[2]
Isometric presses as preparation for explosive power movements[edit]
Isometric presses are instinctively employed prior to various movements in order to aid power production. This is also known as isometric preload or muscular pre-tension. An everyday example is a person getting up off a chair. They first raise their posterior off the chair and then perform a pressing action downwards on their bent legs. As the bent legs resist the downward force upon them in equal measure, an isometric press is generated. From this point, the person then straightens and stands up. A more dynamic example is a vertical jump. Here, the jumper crouches down and adopts a similar isometric press before powering upwards into the jump.[3]The employment of isometric presses in order to aid explosive power movements is also found in sports such as boxing. Here, the boxer may bend their lead leg, while positioning their torso and its respective bodyweight over it, so there exists equal forces between the upwards force of the bent leg and the downward force of the torso. The boxer then throws a lead hook from this position and the forces from the isometric press are channelled into the punch and help to increase its overall power.[4] Such a channelling of force fundamentally represents the purpose of an isometric preload: which is as a preparatory action to aid a subsequent power movement.
- Examples of preparatory isometric presses in sport
The jumper on the left performs a distinctive isometric press, primarily by applying downward pressure onto his bent rear leg. This acts as a means of preloading the muscles prior to engaging in a jump from standing. The jumper to the right of him is mid-flight.
Olympian Ryan Lochte (near) standing on top of the wedged starting blocks. Each swimmer performs a preparatory isometric press by applying downward pressure onto their bent legs. This serves to preload the muscles and helps to make the subsequent dive more powerful.
A sprinter strides forwards from the starting blocks. The blocks helped her to perform an enhanced isometric press and preload her muscles; this allowed her to drive forwards more powerfully and start faster.
Sumo wrestlers just beginning to charge forwards after crouching down and performing an isometric press. The press enables them to charge into their opponent more powerfully, which is especially useful when the match begins.
American Football players line up against eachother and crouch down into an isometric press position. This allows them to rush forwards more powerfully when the play begins; this is particularly useful in regard to tackling or blocking an opponent.
A discus thrower performs an isometric press by applying downward pressure onto his bent right leg. This allows the throw to be performed more powerfully.
A shot putter performs an isometric press by applying downward pressure onto his bent right leg. This will allow him to turn and spring forwards more powerfully, and channel the muscular force generated by the press into the throw.
Forms of isometric resistance and force measurement devices[edit]
Resistance in isometric exercises typically involves contractions of the muscle using:
- The body's own structure and ground (e.g., yoga poses such as Plank or the Warrior variations)
- Structural items (e.g., pushing against a fence or ISOPHIT machine)
- Free weights, weight machines, or elastic equipment (e.g., holding a weight in a fixed position)
- kBox type of isoinertial device
- Pressure-plate-type equipment that has a digital display of maximal force
Depending on the goal of the exercise, the exertion can be maximal or sub-maximal.
History[edit]
Isometric exercises were first brought to the modern American public's attention in the early days of physical culture, the precursor to bodybuilding. Many bodybuilders had incorporated isometric exercises into their training regimens.[5]
Medical uses[edit]
Isometric exercises can also be used at the bedside to differentiate various heart murmurs; the murmur of mitral regurgitation gets louder[6] as compared to the quieter murmur of aortic stenosis.[7] They can also be used to prevent disuse syndrome in a limb that has been immobilized by a cast following a fracture.
NASA studies[edit]
NASA has researched the use of isometrics in preventing muscle atrophy experienced by astronauts as a result of living in a zero gravity environment. Isometrics, muscle lengthening and muscle shortening exercises were studied and compared. The outcome showed that while all three exercise types promoted muscle growth, isometrics failed to prevent a decrease in the amount of contractile proteins found in the muscle tissue. The result was muscle degradation at a molecular level. As contractile proteins are what cause muscles to contract and give them their physical strength, NASA concluded that isometrics may not be the best way for astronauts to maintain muscle tissue.[8]
See also[edit]
References[edit]
Isometric Exercise Examples With Pictures And Pictures
- ^'Article on static strength training'. Sport-fitness-advisor.com. Retrieved 2014-02-26.
- ^Brandon, Patterson (11 September 2013). 'Science of Lifting: Isometrics'. elitefts.com. Retrieved 25 September 2019.
- ^Sharkey, Brian J. & Gaskill, Steven E. 'Preload and Elastic Recoil' in Fitness and Health, Champaign:Human Kinetics, 2007, p.169
- ^Dempsey, Jack, 'Stance' in Championship Fighting Explosive Punching and Aggressive Defense, 1950
- ^'Strength Training - Isometric Exercise'. SPMESSENGER.com. Archived from the original on 2008-01-29. Retrieved 2008-11-10.
- ^Ching, W. 'Evaluation of Cardiac Murmurs in the Clinic Setting'(PDF). University of Chicago. Archived from the original(PDF) on 2008-12-17. Retrieved 2008-01-10.
- ^Cassidy J, Aronow WS, Prakash R (1975). 'The effect of isometric exercise on the systolic murmur of patients with idiopathic hypertrophic subaortic stenosis'. Chest. 67 (4): 395–397. doi:10.1378/chest.67.4.395. PMID1168115.
- ^Barry, PL; Phillips, T (2004-10-12). 'Why do Workouts Work?'. NASA. Retrieved 2008-01-10.
Famed strongman Alexander Zass credited much of his great strength to his isometric training as a prisoner during World War I. He would push on the bars and chains that held him captive and quickly saw benefits. Not long after, he started promoting this method of training through his mail order courses.
What Is Isometric Training?
In simple terms, muscle can only contract in a few ways. It can do the obvious and contract to shorten the distance between joints, such as when doing a bicep curl. This is called a concentric contraction, where the muscle tenses while shortening.
It can also tense while lowering a load, or resisting it, such as when lowering the weight in a curl. This type of contraction is known as eccentric and occurs when the muscle tenses while lengthening. A final type of contraction is called an isometric contraction, and it occurs when the muscle tenses while not changing length. Examples of this are poses in body building or pushing against an immoveable object such as a wall.
List Of Isometric Exercises
One of the main benefits of isometric training is that the body is able to activate nearly all the available motor units - something that is usually very difficult to do. Back in the 1950s, researchers Hettinger and Muller found a single daily effort of two-thirds of a person’s maximum effort exerted for six seconds at a time for ten weeks increased strength about 5% per week, while Clark and associates demonstrated static strength continued to increase even after the conclusion of a five-week program of isometric exercises.
Another benefit of isometric training is simply the amount of time spent performing an exercise. Consider an exercise like the bench press. It may take one to two seconds to perform with each joint angle only being trained for short periods of time.
Isometric Exercise Examples With Pictures
In contrast, an exercise that mimics the bench press, like a press against pins at the sticking point of the lift, may be performed for several seconds. In other words, if you have a problem at a particular joint angle in a lift, you can do targeted isometrics to quickly overcome your problems.
Given that you can perform isometrics with little equipment and a relatively short timeframe, you’d think they’d be far more popular in the training world. So why aren’t they mainstream? For starters, there’s no denying the commercial aspect.
With isometrics there’s no valuable equipment to sell. Secondly, there has been some selective use of the science involved in isometric research. Many will cite potential drawbacks such as decreases in coordination and speed of movement or decreases in muscle elasticity.
Like all good training methods, you need to know how and when to apply isometrics, and how to overcome whatever shortfalls it has. Every system has holes and it is your job as the trainer to overcome them.
Potential decreases in muscle elasticity and speed of movement are easy to overcome with the use of relaxation and stretching methods between sets. The famous RKC Fast & Loose drills apply here, as would something even as simple as pranayama from yoga or even jumping rope.
One of the biggest issues people often cite is that isometrics will only work at that specific joint angle. However, Mel Siff noted in his book Supertraining:
…isometric training also produces significant strength increase over a range of up to as much as 15 degrees on either side of the training angle. Moreover, as with all strength measurements, there is a specific force or torque versus joint angle curve for each type of muscle contraction, so that it is highly unlikely that a strength increase would be confined to a very precise angle and nowhere else in the range.
In other words, it is more likely than not that strength gained at one joint angle will carry over to others. The caveat is that this seems most likely when the joint is at its most lengthened and the regional specificity of isometric training is most noticeable when the muscle is at its shortest.
How to Use Isometrics
I’m going to give you two versions of application. Both will work, but one will require some equipment and the other can be done on your own. The equipment variation is suitable for someone looking for fast increases in strength, while the solo version can be used for performance but is also great for injury rehabilitation.
Version #1: Isometrics With Equipment
To do the equipment variation you’ll need a bar, a bench, a power rack, and a lot of weight. We’re going to use three exercises - the bench press, squat, and deadlift.
Bench press and squat: To perform these two we’re going to set the bar on one set of pins at the mid-range of the movement, usually where a sticking point occurs, with a second set of pins slightly above it. You don’t even need load on the bar for either of these variations. On most power racks simply set the second set of pins at the next available height. Performing the isometric contraction is simple. Assume your position with either the squat or the bench press and drive the bar into the higher set of pins as hard as you can for six to eight seconds.
Deadlift: To perform the deadlift variation load the bar with a weight that is well beyond your one-rep max. It is important that the bar will not budge at all once you start the pull. (As a side note, you will get a lot of looks at the gym when you just load plate after plate after plate onto the bar). Like with the bench and squat variations, you will pull as hard as possible for six to eight seconds.
Version #2: Isometrics With Bodyweight Only
The main problem many will have with these bodyweight variations is the lack of sensation of actually pushing or pulling the weight. These exercises are performed as static contractions in a single position.
The three exercises to be used are the squat, lunge, and push up. For any of the three, assume a position midway through the range of movement and tense everything you can in your body as hard as possible. What makes this tricky is that not only will you have to tense what would be the agonists (the muscles contracting while you squat or lunge), but also the antagonists (muscles that oppose the action, such as the back in the push up).
My experience is that many people don’t have good enough body control to be able to execute this well. Regardless, many will still find that a single rep is spent chasing tension around the body.
As soon as you have one thing tight, you’ll realize that your calves aren’t turned on, and then that will switch your glutes off, which in turn will cause you quads to let go, and on and on. With practice this chase does go away and you will become more skilled at getting everything switched on quickly and fully, which is the exact purpose of this training - to teach you to recruit more motor units.
Conclusion
In either plan, you can change the joint angle workout-by-workout, or week-by-week to minimize any potential loss of ability at different angles. For the deadlift, either raise the bar a few inches or work from a slight deficit in successive workouts.
Russian sports science great Yuri Verkhoshansky recommended that isometric workouts be limited to ten minutes per session. This would be total time of isometric contraction for the whole workout, so for example, if you did 3 x 10 second holds in each position (for either workout) you’d have done ninety seconds total.
The greatest success I’ve had with people is working up to five sets of ten-second contractions in each position. I know that is well short of the maximum ten minute time span, but if you do these right, meaning that when you turn everything on you really make sure to tense everything maximally, you will find your CNS can’t handle too much more.
I generally recommend people start with three six-second contractions for each exercise and add a rep per week, before adding time to the length of each rep. In between reps perform Fast & Loose drills, breathing exercises, shadow box, or anything else that will shake off the muscle tension.
Isometric sessions should be used just like regular strength training with peak frequency for the week at around three to four sessions. Be careful with how much you do. These sessions won’t leave you sore or tired, but CNS fatigue is easily hidden. It can take the nervous system up to five times longer to recover than the muscular system, so the effects of isometric training can last a long time after your session.
I had a volleyball player who was on an isometric program years ago. We were using the bodyweight plan to get his knees back up to speed after an injury. In a single week he hit the session five times and then wondered why he couldn’t play on the weekend. The CNS fatigue from many all out maximal attempts during the week had seen him unable to serve a single ball in during a tournament! So, take heed - isometrics work, just use them like any other high intensity method, and a little goes a long way.
References:
1. Mell C. Siff, PhD, Supertraining (Denver: Supertraining Institute, 2004), 401
Photos courtesy of Shutterstock.