HIT, an acronym for high intensity training is a misnomer, all training to be effective must have a combination of volume and intensity. To term training high intensity training is a misnomer, because high neural demand activities demand high intensity. This is not the exclusive domain of resistance training.
The primary arguments for the HIT method are that it is safer and faster.
Concentrating forces at one joint that should be distributed over multiple joints is not safe. Also the machines do not fit people that are more than two standard deviations outside of ?normal,? whatever that is. This is unsafe because the axis of rotation of the machine is outside the joint axis, once again putting undue stress on a joint. As far time utilization only one person can use one machine at a time. This results in too much standing around. Also it takes a series of machines to do a complete workout. Bodyweight, dumbbells and free weight can be easily adapted to the size of the group. As far as I am able to determine through my experience and research is that HIT is a sound method to use for six to eight weeks to gain bulk. The muscle isolation creates a hypertrophic response, it is essentially body building. As far as the one set to failure concept. Bill Kraemer did a very good job of refuting this argument in a published study reporting the results of a longitudinal training study. The study clearly showed that multiple stets were more effective.