Go Dood!
This is a summary of the recomendations in that paper:
• Select a mode of exercise that feels comfortable throughout the range of motion. There is very little evidence to support the superiority of free weights or machines for increasing muscular strength, hypertrophy, power, or endurance.
• Choose a repetition duration that will ensure the maintenance of consistent form throughout the set. One study showed a greater strength benefit from a shorter duration (2s/4s) and one study showed better strength gains as a result of a longer duration (10s/4s), but no study using conventional exercise equipment reports any significant difference in muscular hypertrophy, power, or endurance as a result of manipulating repetition duration.
• Choose a range of repetitions between three and 15 (e.g., 3-5, 6-8, 8-10, etc.). There is very little evidence to suggest that a specific range of repetitions (e.g., 3-5 versus 8-10) or time-under-load (e.g., 30s versus 90s) significantly impacts the increase in muscular strength, hypertrophy, power, or endurance.
• Perform one set of each exercise. The preponderance of resistance-training studies shows no difference in the gains in muscular strength, hypertrophy, power, or endurance as a result of performing a greater number of sets.
• After performing a combination of concentric and eccentric muscle actions, terminate each exercise at the point where the concentric phase of the exercise is becoming difficult, if not impossible, while maintaining good form. There is very little evidence to suggest that going beyond this level of intensity (e.g., supramaximal or accentuated eccentric muscle actions) will further enhance muscular strength, hypertrophy, power, or endurance.
• Allow enough time between exercises to perform the next exercise in proper form. There is very little evidence to suggest that different rest periods between sets or exercises will significantly affect the gains in muscular strength, hypertrophy, power, or endurance.
• Depending on individual recovery and response, choose a frequency of 2-3 times/week to stimulate each targeted muscle group. One session a week has been shown to be just as effective as 2-3 times/week for some muscle groups. There is very little evidence to suggest that training a muscle more than 2-3 times/week or that split routines will produce greater gains in muscular strength, hypertrophy, power, or endurance.
In reality, progression in resistance training is simply adding enough resistance, which is a consequence of getting stronger—not a requisite—to stay within the desired range of repetitions and maintain a specific degree of effort. This is achieved while maintaining the precise exercise form for each aspect of the chosen protocol. Complex manipulation of any or all of the previously discussed resistance-training variables in an attempt to enhance gains in muscular strength, hypertrophy, power, or endurance in novice, intermediate or advanced trainees is primarily based on unsubstantiated opinions, and lacks sufficient scientific evidence - empirical or theoretical - for support.