1. Case Study - Eight Performance-Based Interval Training Sessions Improves
Chest Press Strength by 19% and Endurance by 140% in a Well-Trained Subject
Ryan Upper, P-BIT Institute, Feb 2017
Key Points:
● Strength improved 60% more, using 56% fewer training sessions, than a comparison
study.
● Training sessions resulting in 67% more repetitions in 50% less time while using the
same external resistance (6RM) as a comparison study.
● Training once a week with the new method resulting in larger strength improvements
than training three times a week using traditional methods.
● The subject completed 52 repetitions of a tested 8RM resistance in 8 minutes, 45
seconds.
Introduction
Traditional weight training programs seem to prescribe training methods that are very different
from all other sports training methods. The process of completing each set, or training instance,
to failure is not present in the majority of sports practice programs. From a sports coaching
perspective, not a weight room coach perspective, if an athlete completes 10 repetitions to
failure using their 10 repetition maximum (10RM) this instance would be considered a test or
"time trial" not a repeatable practice item. In swimming and track running, athletes rarely
perform a single continuous action to failure (3, 9). Instead of showing up to practice every day
and performing a 200-yard swim for best time, swimmers perform repetitions using a fractional
distance while preferable maintaining a specific power output (3, 15). Failure occurs at a point
where the volume of distance has greatly exceeded the distance of the continuous competitive
event.
Studies have been published that hint at this inconsistency. Haff et al. briefly experimented with
cluster set training but relegated the concept to “program variation” and for power development
sessions (5). [It needs to be noted that almost all sports are power dependent in which the
sport-specific power requirements will fall within narrow event-specific ranges. Competitive
weightlifting is a strength dependent sport requiring only one brief instance of movement-limited
athleticism near 100% maximum effort; bodybuilding is an aesthetic sport that is judged without
a power requirement criteria.] Iglesias-Soler et al. expanded on the cluster concept and showed
that many more repetitions of a near-maximal resistance (4RM) could be completed using
cluster sets. The study also demonstrated a higher average velocity (the resistance was defined
so this could have also been viewed as “power”) but relegated the results to improving
endurance needs in wrestling and judo (7) despite proving the capability of humans to complete
a large volume of work using a near-maximal resistance in a fairly efficient manner.
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2. Forty years ago, Harris et al. wrote that the phosphocreatine (PC) resynthesis half-time was
around 22 seconds. This initial recovery, the alactic fast-component, almost always replenishes
about half of the expended PC while the remaining debt may take 3-10 minutes of rest to
regenerate (6) due to the energy transport system slowing down 20-30 seconds after a work
period is completed. The current case study seeks to find a new, more efficient, ratio of energy
recovery to expenditure by maintaining activation of the alactic fast-component system using
factional-maximum sets (5, 7, 21) while adhering to a 22-second rest ceiling. This concept
contradicts most existing recommendations of 3-5 minutes of rest for near-maximal continuous
effort training (4, 10-13, 16, 20). This design is more consistent with methods most other sports
use for event-specific performance.
Case Study Intervention
In the current case study, one male recreational athlete was tested in the bench press using a
resistance estimated to be the athlete’s 6 repetition maximum (6RM). The subject was 36 years
old (71 inches, 190 pounds), a well-trained former collegiate aquatic athlete (swimming and
water polo, 20 years of experience in both), and the subject recently had one continuous year of
weight training experience. The subject also trained for swimming or water polo 2-3 times a
week using either the Ultra-Short Race Pace Training (USRPT) method (15) or Ultra-Short
Water Polo Training (USWPT) method (18).
The pre-intervention test was performed on a Smith guided-barbell apparatus. Warm up
consisted of approximately 5 minutes of lifting using various exercises, including the Smith flat
chest press, with light resistance. The subject then performed one repetition using the tested
weight to initiate muscle familiarity. After one minute of rest, one more repetition was completed
and the subject lightly stretched for two minutes. The subject then completed 5 continuous
repetitions at 205 pounds and failed to complete repetition number 6.
The experimental design used the Performance-Based Interval Training (P-BIT) method in a
"multi-component anaerobic design" which is an advanced P-BIT program (1, 2, 19). In the first
training session, while performing the Smith flat chest press, the subject performed 2 repetitions
at 205 pounds on a 20-second interval (adjusted). Sets were completed until the subject could
not complete 2 repetitions (performance failure) and were performed as fast as possible (no
pause or slow repetitions). After three failed sets the subject concluded the session [2, 205, :20,
19 total sets]. Sessions were scheduled once a week for 8 weeks. No other chest press or
triceps exercises were attempted during the intervention. Each session was modified based on
the previous session performance according to standard P-BIT progression tables (19). The
subject conducted 8 training sessions before post-intervention testing.
During the first training session, the subject completed 13 sets at 205 pounds to initial muscle
failure and attempted 19 total sets by the ​third muscle failure [2, 205, :20, 19]. During the final
training session, the subject completed 26 sets at 225 pounds by the ​first muscle failure [2,
225, :20, 26]. The final training session was concluded without attempting more sets to failure
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3. due to the volume of work already completed within the session. After 8 training sessions, the
subject conducted a repetition to failure test using the resistance from the final training session.
Table 1: Training session log
Exercise Resistance Repetitions Interval in
Seconds
First Failure
Set
Total Sets
Attempted
smith flat bench 205 5 RM Test 1 1
smith flat bench 205 2 20 13 19
smith flat bench 205 2 20 19 23
smith flat bench 215 2 20 13 19
smith flat bench 215 2 20 25 25
smith flat bench 225 2 20 9 14
smith flat bench 225 2 20 10 16
smith flat bench 225 2 20 18 21
smith flat bench 225 2 20 26 26
smith flat bench 225 8 RM Test 1 1
smith flat bench 205 12 RM Test 1 1
Results
One week after the final training session the subject attempted a post-intervention RM test using
the resistance from the final training session. The subject warmed up for two minutes on a
stationary bike and achieved a heart rate of 140 bpm. The subject completed 6 repetitions at
145 pounds followed immediately by one repetition at 225 pounds to initiate muscle familiarity.
After one minute of rest, the subject completed one additional repetition at 225 pounds and
stretched lightly for two minutes. The post-training RM test resulted in 8 unassisted repetitions
using 225 pounds. This result fell within normal parameters of P-BIT theory. Using the NASM
RM percentage guide (22), it is estimated that the subject's 5RM resistance was 245 pounds or
a 19% improvement over the pre-intervention results.
After 72 hours of recovery from the post-intervention test, the subject completed another
repetition-to-failure test using the pre-intervention resistance of 205 pounds. The subject
warmed up for two minutes on a stationary bike and achieved a heart rate of 140 bpm. The
subject completed 6 repetitions with 145 pounds followed immediately by two repetitions at 205
pounds to initiate muscle familiarity. After one minute of rest, the subject completed one
additional repetition at 205 pounds and stretched lightly for two minutes. The subject completed
12 continuous unassisted repetitions at 205 pounds. The endurance improvement over the
initial pre-intervention resistance was 140%.
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4. Discussion
The resulting strength improvement is greater than improvements recorded in previous studies
(4, 16) including a study of similar length and test criteria (4). Drinkwater et al. showed an
improvement of 7.3 kg in strength for a traditional 6RM intervention (4 sets of 6 repetitions) that
included an average of 1.0 failures per training session. This study also experimented with a
"broken" or cluster set (5) training configuration (8 sets of 3 repetitions) using a 6RM resistance
that did not result in reported repetition failures (0.0 average) and only a 3.6 kg increase in
strength (4). The method used in the current case study accomplished 2.25 failures per training
session and resulted in a 9.1 kg increase in strength in conjunction with a 60% increase in
repetitions during the post-intervention test at 225 pounds. Conversion of an 8RM resistance of
225 pounds to a 5RM resistance is estimated to be 245 pounds (22). A post-intervention 5RM
test may have resulted in an 18.2 kg improvement in strength after only 8 training sessions.
The second important result of this case study is the difference in time commitment per session
required to achieve similar improvements (4, 10-13, 16, 20). Drinkwater et al. conducted chest
press training sessions 3 times a week for 6 weeks and Schoenfeld et al. conducted 24 training
sessions over 8 weeks (4, 16) while the current intervention was performed once a week for 8
weeks for 8 total sessions. The time commitment for each P-BIT session was reduced and only
a single chest press exercise was attempted each week. The P-BIT sessions used an adjusted
mean time of 6:45 to complete an average of 40.5 repetitions of a 5-8RM resistance while the
Drinkwater et al. intervention time was fixed at 13:20 for 24 repetitions. The subject in the
current case study performed 67% more repetitions in 50% less time using the same
percentage of external resistance as Drinkwater et al.
The subjects in Schoenfeld et al. completed 24-36 repetitions of an 8-12RM resistance in
approximately 7:30. In the current case study, the longest P-BIT session was 8:45 (adjusted)
resulting in 52 repetitions at 225 pounds (the eighth and final session) which was tested to be
the subject's 8RM one week later. Greatly improving strength using only one exercise session
per week seems to contradict more established training frequency principles as well (17).
Conclusion
Eight Performance-Based Interval Training (P-BIT) sessions improved chest press strength in a
well-trained subject by 19% as well as chest press endurance by 140%. During training, more
repetitions, using near-maximal resistance, were completed in less time than training sessions
performed in similar studies using more traditional training methods. P-BIT appears to improve
chest press strength with less than half the time commitment of other methods.
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Ryan Upper
ryan.upper@gmail.com | 02/13/2017
blocksign.com/v/UetuE5Km05fAX6OM