Q&A: Criticisms of Training to Failure

Question:

Hey Drew,

I’m really looking forward to your new book. I read a few comments from people who advise against HIT and I hope you could respond to them. I’m hoping your book will respond to similar questions and comments as well. Here they are:

Noted exercise scientist Paul Ward warns that training to failure results in ischemic reperfusion, or oxygen deprivation, followed by oxygen perfusion. This results in massive free-radical damage to DNA and cell membranes.

International Sports Sciences Association co-founder Dr. Sal Arria cautions that many soft tissue injuries occur when failure terminates a repetition in mid-stroke. “When the weight on the bar exceeds the muscle’s ability to lift it, something has to give and usually, it’s the musculotendinous junction.

Louie Simmons, well known coach to many elite-level power lifters finds that taking sets to failure “has an ill-effect on the central nervous system,” which delays recovery. Simmons is noted for producing scores of high-ranked lifters with relatively low-intensity training.

I know you’ve seen these comments in the past. Could you be kind enough to give a response to these comments?

Answer:

Regarding training to failure and ischemic reperfusion, consider that concentric failure is simply the point in an exercise where fatigue has reduced the strength of the muscles involved to the point where they are no longer capable of shortening against the selected resistance. If a slightly lower resistance was selected and the exercise was stopped just short of failure, the same degree fatigue and associated physiological effects including ischemic reperfusion could have been achieved without failure. There is nothing about training to failure in particular that would make this more or less likely. If anything, overtraining is far more of a problem where free-radical damage is concerned than intensity of training.  If someone is worried about free radical damage they would do better to focus on limiting volume of exercise rather than intensity.

The same goes for the effects on the CNS. The negative effects on the CNS are not due to training to failure, but rather overtraining. The microtrauma caused by training leads to an inflammatory response. If the body is not allowed adequate recovery time between workouts, chronic inflammation results, and cytokines involved in inflammation start to act on the CNS causing the various symptoms associated with overtraining. These cytokines can also affect the hypothalamus, causing increased cortisol levels. I suspect the myth about training to failure and CNS “burnout” resulted from attempts at increasing the intensity of exercise without the necessary reduction in volume.

There is no increased risk of injury when muscular failure occurs during mid stroke. This is complete nonsense. Fatigue reduced the amount of force the muscle can contract with, but has little affect on the amount of strain it can withstand.  A weight you can lift in good form for several repetitions is not heavy enough to tear the involved muscles, whether fresh or fatigued.

Also, muscles are capable of producing more force during static contractions than concentric because slower a muscle shortens the more force it is capable of producing (static is as slow as you can go), and the muscles are stronger in the mid-range position. Both of these have to do with cross-bridges; slower movements allow more cross-bridges to be formed than faster movements (force/velocity curve) and there is more optimal overlap of myofibrils in the mid-range of the exercise also allowing for more cross-bridging. So even if you’ve fatigued the muscles enough to prevent further positive movement, you are more than strong enough to hold the weight as well as to lower it under control.

Over the past 15 years I have put hundreds of people through tens of thousands of high intensity training workouts, and with a few exceptions (initial “break-in” period, working with certain physical problems, etc.) all of them trained to muscular failure on a consistent basis. Not once have any of them been injured or suffered “CNS” burnout as a result of training to muscular failure, and I’m confident whatever free-radical damage they may have incurred as a result of training is far less than what a more conventional, higher-volume routine would have caused, and much of that would be offset by diet if they’re eating enough antioxidant rich vegetables and fruits.