Constant versus Variable Resistance Training
When performing a regular bench press exercise with free weight is considered a form of constant resistance exercise. Constant resistance is a form of training where the resistance directed against the target muscle or muscle group does not vary through the range of athletic movement. The lifting of free weights is an example of constant resistance. In an exercise involving constant resistance, the muscular power generated and the effect of the resistance on the muscle are not constant. An example of the effect of constant resistance is found in the simple curl of a free weight using a conventional dumbbell. At the start of the exercise, the muscles of the arm, primarily the bicep, pull the weight upward. There is a point, as the dumbbell is lifted, where the resistance on the muscle is greatest; at the movement before and after that maximal point, the resistance force is much less. At the conclusion of the exercise, there is little or no resistance being applied to the biceps.
Variable resistance such as bands and chains requires differing degrees of force to be applied to the target muscle to create constant resistance, compelling the muscle to work harder to meet the demands of the exercise. In a variable resistance arm curl, the forces applied to the bicep are variable at each stage of the curl in order to maintain the same resistance throughout the trajectory of movement. Variable resistance exercise is designed to achieve maximum muscular involvement. Inherent in the effectiveness of variable resistance exercise is the relationship between the intensity required of the athlete and the volume of resistance work involved. Resistance exercises are typically carried out through the use of specialized machines that are designed to permit control of the entire force-generating movement.
The machines may be designed for the training of any muscle group in the body. Machines that isolate the pectoral muscles through a seated bench press, deltoid machines, and shoulder extension machines are three of a multitude of models commercially available. The common features of variable resistance training machines are the presence of cables, pulleys, or other devices to create variability, coupled with the placement of the user in a fixed position to ensure that the user cannot recruit other muscle groups to assist in the completion of the prescribed movements. Variable resistance training success is predicated on the principle of regulating the amount of work per unit of training time. One of the world’s best known variable exercise machines is the Universal line, developed in the early 1970s by Dr. Gideon Ariel, a specialist in bio-mechanics. The Universal machines are constructed on the basis of two principles that guide their application in muscle development. The first principle is that resistance exercise is most effective when a multiple number of joints are required to complete the exercise. The second principle is the notion of explosive repetitions—to achieve the maximum level of mental concentration and to obtain the maximum firing levels of muscle fiber for optimal performance.
The engagement of a multiple number of joints in resistance training requires the body develop the strength to counteract the forces applied by the machine throughout the entire range of motion in each repetition. When those repetitions must be performed as rapidly as possible, without sacrificing adherence to proper form or otherwise compromising the desired range of motion, the athlete will be compelled to react with greater speed. The faster that the athlete must react to the resistance directed into the target muscle, the faster the individual muscles will fire. This approach mirrors the other training methods that are used by athletes to develop the capabilities the fast-twitch fibers present in each muscle.
Any Science to Using Bands and Chains?
The use elastic bands and weighted chains has received widespread recognition and increased popularity within recent years among powerlifters for increasing bench press and squat strength. Elastic bands in the past have been used primarily in rehabilitation settings. Recently, elastic bands have been found to induce greater strength gains than traditional weight training1, 2. Because of the tendency of the elastic bands to pull a barbell down during early phases of a lift, an increased eccentric loading phase occurs, which supports higher eccentric velocities associated with this type of training. Considered a form of nontraditional training, the external resistance using these devices (bands and chains) may be altered to target specific neuromuscular recruitment patterns and enhance strength production. Changing the resistance training modalities such as using traditional bench press movements, an attempt has been made to specifically match the strength curve of a particular exercise movement.
When hanging chains are added to the ends of a barbell, free-weight exercise models characteristics that are similar to variable resistance training devices. Weighted chains alter the kinetics of the barbell during the entire range of movement as well as increasing the mechanical advantage of the movement3,4,5. This system accommodates a lifter by decreasing load at the weakest joint position and increasing the load at the lifter’s strongest joint position. It is hypothesized that weighted chains training would provide optimal resistance throughout the entire range of motion through the accommodation of the changing length-tension relationship of the musculoskeletal system.
Weighted chain training has also been reported as a method for injury prevention because decreased loads occur at the deep squat position, where shear forces on the knee are greatest 6. In addition, because of the progressive decrease in resistance at the end of the eccentric phase, a strength trainer will spend a longer period of time in the acceleration phase at the early stages of the concentric contraction because of lighter loads at this time frame. Furthermore, accommodating resistance techniques are purported to be more advantageous than traditional strength training because of decreased time in the deceleration phase that accompanies traditional free-weight training7. Training methods that shorten the deceleration phase and increase the time the barbell is in peak velocity may increase one’s rate of force development over time.
Bands and Chains Put to the test! Do they Work?
Researchers took healthy young men took 36 Division 1 AA football players and had them perform a 7 week offseason workout program but were assigned to either band training, chains training, or traditional bench press training.
- The chain group used three chains (Westside Barbell, Columbus, Ohio) that were attached to each side of a barbell, for a total of 6 chains on the bar. Four chains consisted of training chains (2 on each side), and 2 were considered support chains (1 on each side). A training chain was 5 ft long and weighed 20 lb. Each 5-ft support chain weighed 4 lb. The combined weight of all chains used was approximately 85-90 lb. The 2 support chains used attached the training chains to the barbell and were lowered to the ground during work sets.
- The elastic band group used elastic bands (Iron Woody Fitness) progressively increase overall resistance during the concentric portion of each repetition. Conversely, during the eccentric portion of each repetition, resistance progressively decreased. The elastic bands were anchored at the bottom of the BP apparatus, creating maximum tension at the top of the lift with lowest tension at the bottom. All 3 groups performed 6 sets of 3 repetitions and were instructed to accelerate the barbell as fast as possible. A qualified strength and conditioning coach closely supervised and tracked training loads and volumes to ensure high-intensity levels, proper technique, motivation, and adherence to the program.
Band and Chain Training Beats Traditional Bench Press Training.
The researchers observed a significant increase in maximum strength in the variable resistance training group (bands and chains) compared with the traditional free-weight training group (bench press). All three groups increased bench press strength but the weighted chains group increased there bench press by 9.6 kg (7%), the elastic bands increased there strength by 10 kg (8%), and the traditional bench press by 7.7 kg (5%). These results suggest that when weighted chains and elastic bands are incorporated into offseason and in-season training cycles, athletes are provided with a unique yet viable method of increasing strength and power variables8. These methods are particularly useful in exercises that mimic ballistic movements, such as the bench press or squat exercise performed explosively. So if you want increase your bench press consider adding some bands and chains to your routine to increase maximal strength.
source:musculardevelopment.com
