Intensity of loading
In research terms, intensity in weight training is defined as the percentage of maximal
capacity that you are lifting (8). Beginners achieve strength gains using weights as low as 50% of
their maximum strength (5). This may allow 20 repetitions or more to be performed.
Advanced lifters will need to use at least 60% of their maximum to obtain strength gains
(5,9). This corresponds to 20 reps or less in most individuals. Maximal strength gains appear to
occur between 4-6RM with lower gains in maximal strength at less than 2RM and greater than
10RM (9). For hypertrophy, it is recommended that lifters work between 60 and 85% of 1RM, as
discussed in chapter 20. This generally falls within the range of 6 to 20 reps. For the greatest
strength gains loads of 85-100% may be used (5). This corresponds to between one and five
repetitions in most people.
In practice, the use of % of 1RM to determine intensity can be problematic since it varies
from exercise to exercise, from individual to individual, and from day to day. In the gym setting,
intensity is typically used as an indication of the overall effort of exercise. By this definition,
higher rep sets (such as 12-15RM) taken to failure can actually be more intense than lower rep
sets (such as a 2-3RM). More accurately, the higher rep set puts a much greater stress on
metabolic factors (such as lactic acid accumulation) while the lower rep set puts less stress on
these same factors (because the set is too short).
Number of reps
There is currently no data to suggest that any one rep range is better than another for the
stimulus of growth. Anecdotally, many authorities suggest a range of 6-20 repetitions completed
in 20-60 seconds as a growth stimulus (4,10-13). The reasons for this time period are discussed
in chapter 20.
There is no need for beginners to use low rep sets early in their training. Recall that the
initial adaptations to strength training are neural. In one study, whether beginners performed
sets of 4-6RM of 15-20RM, they obtained the same adaptations (14). Higher repetitions (no
lower than 8) are recommended for the first several months of training (5). After the first 8-12
weeks of training, beginners may begin working with heavier loads and lower repetitions if desired.
Training volume/number of sets
Volume of training can refer to the total poundage lifted, total number of sets done or total
number of reps done (8). This book will use total sets and reps as as measure of volume,
especially with regards to glycogen depletion and the ketogenic diet.
There is a great deal of debate over how many sets are necessary for optimal results. For
hypertrophy, anywhere from 1 to 20 sets has been used by lifters (4) and 3-6 sets per bodypart
has been suggested as optimal for growth (3,4). However, this depends greatly on individual
recovery capacity and genetics. Some individuals, typically referred to as ‘hardgainers’, may
have trouble recovering from even two or three maximal sets, while others can handle much
higher training loads.