http://link.springer.com/article/10.1007/s00421-012-2511-9
"To compare the effects of a periodic resistance training (PTR) program with those of a continuous resistance training (CTR) program on muscle size and function, 14 young men were randomly divided into a CTR group and a PTR group. Both groups performed high-intensity bench press exercise training [75 % of one repetition maximum (1-RM); 3 sets of 10 reps] for 3 days per week. The CTR group trained continuously over a 24-week period, whereas the PTR group performed three cycles of 6-week training (or retraining), with 3-week detraining periods between training cycles. After an initial 6 weeks of training, increases in cross-sectional area (CSA) of the triceps brachii and pectoralis major muscles and maximum isometric voluntary contraction of the elbow extensors and 1-RM were similar between the two groups. In the CTR group, muscle CSA and strength gradually increased during the initial 6 weeks of training. However, the rate of increase in muscle CSA and 1-RM decreased gradually after that. In the PTR group, increase in muscle CSA and strength during the first 3-week detraining/6-week retraining cycle were similar to that in the CTR group during the corresponding period. However, increase in muscle CSA and strength during the second 3-week detraining/6-week retraining cycle were significantly higher in the PTR group than in the CTR group. Thus, overall improvements in muscle CSA and strength were similar between the groups. The results indicate that 3-week detraining/6-week retraining cycles result in muscle hypertrophy similar to that occurring with continuous resistance training after 24 weeks."
This group had previously studied the effects of shorter term results from a like protocol, which Bryan had posted about a year or so ago. The trend in hypertrophy rates from earlier studies would suggest over time, as we like to believe greater hypertrophy gains should be seen in the train/detrain group. However, even after 24 weeks, muscle CSA is still equal.
Obviously limitations here might be the length of the detraining period, untrained individuals and perhaps just that these expected superior results may just take more time to materialize.
Authors share Bryan's ideas;
"our PTR group exhibited an identical increase in TB-CSA and PM-CSA muscles
during the second retraining period (weeks 18–24). If the
same retraining effects occurred after 24 weeks of training,
and if continuous long-term training induced decreased
muscle adaptations, 3-week detraining/6-week retraining
cycles may produce greater muscle hypertrophic responses
compared with continuous training cycles after 24 weeks.
Our results are in agreement with those of the previous
cellular and molecular studies. Chronic muscle contraction
induces a variety of metabolic and morphological adaptations in contracted skeletal muscles for maintaining
homeostasis and minimizing cellular disturbances during
subsequent training sessions (Gordon et al. 2012; Hubal
et al. 2008). In the muscle, anabolic mammalian target of
rapamycin (mTOR) signaling and protein synthesis
responses to resistance exercise are attenuated by chronic
resistance training (Coffey et al. 2006; Phillips et al. 1999,
2002; Tang et al. 2008). These results may explain the
attenuated muscle hypertrophy response observed during
the late phase compared to the early phase of resistance
training. In contrast, our results suggest that although
greater relative stimulation (i.e., greater intensity, volume,
frequency) would be required to sustain anabolic responses
for further adaptations, these responses would become
sensitive again after a short detraining or non-training
period. These mechanisms may be responsible for
retraining-induced muscle hypertrophy and the advantage
of periodic training programs, at least in young individuals."
"To compare the effects of a periodic resistance training (PTR) program with those of a continuous resistance training (CTR) program on muscle size and function, 14 young men were randomly divided into a CTR group and a PTR group. Both groups performed high-intensity bench press exercise training [75 % of one repetition maximum (1-RM); 3 sets of 10 reps] for 3 days per week. The CTR group trained continuously over a 24-week period, whereas the PTR group performed three cycles of 6-week training (or retraining), with 3-week detraining periods between training cycles. After an initial 6 weeks of training, increases in cross-sectional area (CSA) of the triceps brachii and pectoralis major muscles and maximum isometric voluntary contraction of the elbow extensors and 1-RM were similar between the two groups. In the CTR group, muscle CSA and strength gradually increased during the initial 6 weeks of training. However, the rate of increase in muscle CSA and 1-RM decreased gradually after that. In the PTR group, increase in muscle CSA and strength during the first 3-week detraining/6-week retraining cycle were similar to that in the CTR group during the corresponding period. However, increase in muscle CSA and strength during the second 3-week detraining/6-week retraining cycle were significantly higher in the PTR group than in the CTR group. Thus, overall improvements in muscle CSA and strength were similar between the groups. The results indicate that 3-week detraining/6-week retraining cycles result in muscle hypertrophy similar to that occurring with continuous resistance training after 24 weeks."
This group had previously studied the effects of shorter term results from a like protocol, which Bryan had posted about a year or so ago. The trend in hypertrophy rates from earlier studies would suggest over time, as we like to believe greater hypertrophy gains should be seen in the train/detrain group. However, even after 24 weeks, muscle CSA is still equal.
Obviously limitations here might be the length of the detraining period, untrained individuals and perhaps just that these expected superior results may just take more time to materialize.
Authors share Bryan's ideas;
"our PTR group exhibited an identical increase in TB-CSA and PM-CSA muscles
during the second retraining period (weeks 18–24). If the
same retraining effects occurred after 24 weeks of training,
and if continuous long-term training induced decreased
muscle adaptations, 3-week detraining/6-week retraining
cycles may produce greater muscle hypertrophic responses
compared with continuous training cycles after 24 weeks.
Our results are in agreement with those of the previous
cellular and molecular studies. Chronic muscle contraction
induces a variety of metabolic and morphological adaptations in contracted skeletal muscles for maintaining
homeostasis and minimizing cellular disturbances during
subsequent training sessions (Gordon et al. 2012; Hubal
et al. 2008). In the muscle, anabolic mammalian target of
rapamycin (mTOR) signaling and protein synthesis
responses to resistance exercise are attenuated by chronic
resistance training (Coffey et al. 2006; Phillips et al. 1999,
2002; Tang et al. 2008). These results may explain the
attenuated muscle hypertrophy response observed during
the late phase compared to the early phase of resistance
training. In contrast, our results suggest that although
greater relative stimulation (i.e., greater intensity, volume,
frequency) would be required to sustain anabolic responses
for further adaptations, these responses would become
sensitive again after a short detraining or non-training
period. These mechanisms may be responsible for
retraining-induced muscle hypertrophy and the advantage
of periodic training programs, at least in young individuals."
Last edited:
