High-intensity strength training is the cornerstone of any successful athlete’s training regimen. It’s no secret that building muscle is a key aspect of improving performance in virtually any sport, as well as everyday life. While the street to making gains is a one-way road, this road has two lanes; the isotonic resistance lane and the elastic resistance lane. Which one should you drive down? Turns out, you might not have to choose.
The merits of isotonic and elastic resistance
Working with traditional weights and elastic bands are two notably different experiences. Throwing around some iron seems like it should be much more beneficial than grabbing a little band; however, multiple studies have shown that elastic resistance can produce the same amount of resistance as traditional weights. The muscular strength curve produced by both isotonic and elastic resistance result in an identical bell-shaped curves, proven by Hughes and his colleagues back in 1999, and solidified again in 2016.
Those two aren’t the only examples of the equivalence of elastic and isotonic resistance; we’ve got a whole list of research studies showing that EMG, torque and outcomes are the same.
Where these two tools differ is found in the pattern of external force. Traditional weights like free weights provide a constant force, while elastic resistance generates more force as the band is elongated (Aboodarda et al. 2016). Therefore, the more a band is stretched, the more force is produced. The amount of resistance is proportional to the amount of elongation, producing a linear increase in force.
Based on this data, can we consider elastic resistance bands to be the ultimate weight-training tool? Not exactly. Back in 2011, the author of a study comparing the muscle torque and electromyographic activity during high intensity elastic resistance and free weight exercises concluded that “one unit of the commercially produced elastic tubing cannot possibly provide adequate external force necessary to accomplish high exercise resistance training for an elite athlete” (Aboodarda et al. 2011). However, the author continued with a counter argument, suggesting:
“Alternatively, the length of elastic material concerned may be shortened to require an increased force of ‘stretching’ to approximate the force required for training purposes… These data disclose the importance of reducing the initial length as an essential strategy to develop muscle activation and torque production when using an elastic resistance device” (Aboodarda et al. 2011).
For example, if you complete a bicep curl with the TheraBand CLX in the 5th farthest loop from the anchor, it would be much easier than performing the curl in the 3rd farthest loop. This coincides with the proven linear force elongation pattern of the elastic resistance; the closer the action is to the anchor, the quicker the band will reach 100% and 200% elongation, resulting in higher resistance earlier in the range of motion.
One road, two lanes, unlimited results
So, we come to the answer of the question posed at the beginning of the article; which tool is better for strength training in athletics: isotonic or elastic resistance? After all of this data, we have to conclude that both tools are effective in the pursuit of higher strength and power, and the choice is up to you. Got a gym full of weights? Nice, get lifting! On the go and don’t have access to a weight room? Pack some bands in your bag and you’ll never have to worry about being gain-less again. With these two options at your disposal, you can be confident that you’re twice as likely to improve your performance and become the champion you know you can be.
Aboodarda et al. 2011. Resultant muscle torque and electromyographic activity during high intensity elastic resistance and free weight exercises European Journal of Sport Science 1-9.
Aboodarda et al. 2016. Muscle activation comparisons between elastic and isoinertial resistance: A meta-analysis. Clin Biomech (Bristol, Avon). 39:52-61.