So I have always felt that there must be diminishing returns to scale for multiple sets when working out. It certainly seems illogical that doing 10 sets would net you gains 10x better than one set. But while on EXRX.net I found an article that seemed to cite some interesting studies?

Quote Originally Posted by exrx.net
The ACSM Weight Training Guidelines state more than one set may elicit slightly greater strength gains but additional improvement is relatively small (ACSM 1995). Studies demonstrating marginal improvements in strength with more sets typically use one exercise per muscle. Split programs performed by experienced weight trainers typically incorporate two or more exercises per muscle group. Fleck and Kramer's review of the literature suggests the optimal number of total sets are between 2 and 5 sets (Fleck & Kraemer, 1997). A second set seems understandable since a warm up set may allow greater intensity for the the following workout set (Shellock & Prentice, 1985).
Certainly this seems to contradict popular theories on how volume works and appropriate training to see hypertrophy and strength gains.

Quote Originally Posted by exrx.net
Many scientific studies demonstrate one set is almost effective as multiple sets, if not just as effective in strength and muscle hypertrophy (Starkey, Pollock, et. al. 1996). These studies have been criticized for using untrained subjects. Hass et. al. (2000) compared the effects of one set verses three sets in experienced recreational weightlifters. Both groups significantly improved muscular fitness and body composition during the 13 week study. Interestingly, no significant differences were found between groups for any of the test variables, including muscular strength, muscular endurance, and body composition.

A few maverick fitness authorities and professional bodybuilders have advocated high-intensity, very low-volume training. Author Jones, the founder of Nautilus and MedX weight training equipment, was one of the early pioneers of single-set training. In the 1980's, Casey Viator, the youngest Mr. America and Mr. Olympia contestant, and Mike Mentzer, Mr. Universe and Mr. Olympia contestant, promoted the high-intensity, low-volume training. More recently, Dorian Yates, several-time Mr. Olympia, reportedly performed only a warm-up set and one or occasionally two workout sets throughout his off-season training.
Has anyone tried doing just single or double (working) set workouts? I'd be tempted to try but you'd only be able to tell whether it was working after a few weeks and by that time you might have wasted a month of what could have been solid training. I know for me it has always seemed that consistency (ie how much workouts per week) has been the most important factor whereas the # of sets doesn't seem that important as long as I get a few in for each workout.

Anyone with any knowledge of this subject able to shed some light? Thanks in advance.