https://onlinelibrary.wiley.com/doi/abs/10.1111/sms.13775From weightlogy August 2020 research review
Interesting thing is the 0% velocity loss group that only did 3 sub-maximal singles each training session still got bigger and stronger
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THE STUDY
Subjects were 62 young men with at least
1.5 years training experience in the bench
press. They were randomly assigned to one
of 4 training groups:
• 0% velocity loss (15 subjects)
• 15% velocity loss (16 subjects)
• 25% velocity loss (15 subjects)
• 50% velocity loss (16 subjects)
Subjects trained twice per week for 8
weeks. At each session, they did 3 sets of
bench press with 4 minutes rest. All groups
performed the bench press at the same
relative intensity (70 - 85% 1-RM). Subjects
did 70% 1-RM for the first 5 sessions, 75%
1-RM for sessions 6-10, 80% 1-RM for
sessions 11-14, and 85% 1-RM for sessions
15-16. Subjects performed each set until
they exceeded the target velocity loss for
their respective group (the 0% velocity loss
group did one rep per set)
Hypertrophy. All groups experienced a
significant increase in pec size (Figure 1).
The 50% velocity loss group had significantly
greater gains than the 0% loss group and measurements
nearly significantly more than the 15% loss
group (Figure 1). The difference between
25% and 50% loss was not statistically
significant (Figure 1).
Strength. All groups significantly improved in
maximal isometric force and in 1-RM, with
no significant differences between groups
This study showed that hypertrophy was
better once you reach a certain velocity
loss threshold. In this study, it was 25%
velocity loss from the first rep. There was
no significant difference between 25 and
50% velocity loss. For example, the 25%
velocity loss group did 5 reps with 70%
1-RM, while the 50% velocity loss group did
8.3 reps. While we don't know how many
Reps in Reserve (RIR) each group had, we
can estimate based on previous research. In
another study, 70% 1-RM of a bench press
to failure was around 12 reps on average.
Thus, we can estimate that the 50% velocity
loss group was probably around 4 RIR, and
the 25% velocity loss group was around 7 RIR.
Thus, the 25% velocity loss group did
only around half the reps they were capable
of when training with 70% 1-RM, and still
had similar hypertrophy to the group that
trained closer to failure (but still probably
around 4 reps shy).
Of course, the RIR is likely load dependent
here. If we look at the previous study again,
average reps to failure with 80% 1-RM in a
bench press was 7.7. Subjects in this study
did 3.4 reps in the 25% velocity loss group
and 5.5 reps in the 50% velocity loss group.
Thus, the 25% velocity loss group likely
trained around 4 RIR, and the 50% velocity
loss group likely trained around 2 RIR. As
a percentage of maximal reps, though, it's
similar. The 25% velocity loss group did
roughly 40-50% of their maximal reps, and
the 50% velocity loss group did roughly 70%
of their maximal reps.
The results of this study are in agreement
with other research indicating you need to
reach a minimal velocity loss threshold to
maximize hypertrophy. The current study
suggests 25%, this study suggests 20%,
and this study suggests 40%. This means
that you do need to experience a certain
amount of fatigue to maximize hypertrophy
of your "high-threshold" muscle fibers (the
muscle fibers with the greatest capacity
for hypertrophy that are only typically
recruited with higher loads or when getting
close to failure with light loads). However,
you don't need to maximize fatigue. This
pokes big holes in the "hypertrophic reps"
or "effective reps" concept, at least when it
comes to trained individuals using compound
movements.
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RACTICAL APPLICATION
Velocity loss can be used on the bench
press as an objective way to determine how
short of failure to train. A threshold of 25-
50% velocity loss can maximize hypertrophy
while managing fatigue. A 25% velocity loss
will be roughly equivalent to 40-50% of your
max reps with moderate to moderately-
heavy loads (70-85% 1-RM).
A 50% velocity loss will be roughly equivalent to 70% of
your max reps, or 2-4 RIR. It may be different
for other exercises or loads. If you don't
measure rep speed, you can try timing your
reps and stop when your concentric reps
roughly double in length. An alternative
would be to stop your sets when you have a
noticeable slowdown in rep speed.
Finally, highly submaximal training may be
useful. You can have "minimal velocity loss"
days in a periodization scheme as a form of
easy days to help facilitate recovery while
maintaining gains.
