Accommodating Resistance
A couple of points...
1) It allows you to maximize your Power Output with Power and Speed Training; develop it through a greater range of the movement in Traditional Strength Training Exercises like Squats, Bench Press, Leg Press, Deadlift, etc
2) It allows you to overload the muscles in though a greater range of motion in Limits Strength and Hypertrophy Training.
In all exercises only one-third of the movement overloads the muscles. The remaining two-thirds of the movement underloads the muscles. Underloading provide a training effect but not as much as Overloading them does.
Muscle fibers that are not trained are not developed.
Chains, Bands and Bungees
1) Chains: You an usually pick them up at some place that caters to heavy construction. I purchased mine from IMSCO (Industrial Mine Supply Company). You can get some fairly heavy chains for a reasonable price from companies that cater to heavy construction.
Chains are over priced by most fitness companies and the cost of shipping is high.
Secondly, most fitness companies sell them with special Olympic Bar Collars that drive up the price and aren't worth it.
It better to get smaller chain to loop around the larger chain. That allows you to vary the length of the chain, as you like based on your height and where you want to increase the loading in the movement.
It also allows you to place them on the inside of the Olympic Bar, then load the plate behind them.
The chain sold by fitness companies with the collar involve loading the plates first, then putting the chains on last, behind the plates.
This is a real pain. Constantly having to take the chain of off to increase the weight on the bar , then them back on.
Attaching the smaller chains to the larger chains allows your varying the resistance with the chain length. It elicits a slightly different training response. Another topic for another time.
2) Bands: You can purchase them anywhere. I use and recommend the smaller and medium strength bands.
The resistance and be increased by wrapping the band around the bar two or three time more.
You can also Reverse Load the Bands. Attach them to the top of a Power Rack, then increase the bar weight.
3) Bungees: This work the same as the Band. I purchased them years ago from Mike Berry/Strength Systems. Mike passed away year ago. The company is no longer around.
Berry had a special Bench Press Bungee Set Up. You hook a strap to the based of the Bench Press. You attached the Bungees to the anchor and then to a Daisy Chain that is attached to the bar. The Daisy Chain has three loops that allows you to increase the tension or decrease the tension based on close or farther the Bungee is attached to the bar.
Picture below
Base Bench Press Daisy Chains
C.A.M.P. USA Daisy Chain Twist | REI Co-op
REI or a store that caters to climbers has these Daisy Chain that will probably work for the base.
Bar Bench Press Daisy Chains
Daisy chain loops for pulling, chins, lifts - IronMind-www.ironmind-store.com
These IronMind Daisy Chains/Loops are wrapped around the bar, allowing you to hook the Bungees to them.
Bungees
Available everywhere.
Research Report
The research and anecdotal make the case for employing them in some part of your training as a way of optimizing Speed, Power, Limits Strength and Hypertrophy Training.
Why perform an exercise that only overloads the muscles in one-third of the movement when you can overload it in close to 100% of the movement?
More is definitely better in this case.
Kenny Croxdale