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(jwbond @ Feb. 18 2008,16:09)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">Have there ever been any studies with rest periods relation to hypertrophy?</div>
I don't know if these really address your question, Batman, but ....
J Sci Med Sport. 2007 Dec 17 [Epub ahead of print] Links
Effects of rest duration between sets of resistance training on acute hormonal responses in trained women.
Bottaro M, Martins B, Gentil P, Wagner D.
College of Physical Education and Exercise Science, University of Brasilia, Brazil.
This study investigated the acute hormonal response to three different rest periods between sets of a traditional lower body resistance training session in young women. Twelve healthy trained females (26.83+/-3.93 years) participated in the study. On three separate sessions of a lower body resistance exercise protocol, subjects were assigned in a random order a rest interval of 30s (P30), 60s (P60) or 120s (P120) between sets. The resistance exercise session consisted of four lower body exercises with three sets performed until contractile failure using 10-repetition maximum (RM) load. Blood samples were drawn for determination of serum growth hormone (GH) and cortisol concentrations before exercise (T0), immediately after each training session (T1), and after 5min (T5), 15min (T15), and 30min (T30) of recovery. Statistical evaluation of the area under the time-concentration relationship for GH (GHauc) and for cortisol (Cauc) were analyzed using a one-way ANOVA There were no differences among protocols (P30, P60 and P120) in the serum GH and cortisol concentrations at baseline (T0). However, as compared to T0, all protocols led to acute increases (p<0.05) in serum GH concentrations after each training session. The GHauc was greater for P30 than for both P60 and P120, however, there were no differences between P60 and P120. The Cauc were not different among protocols. Thus, the magnitude of acute GH responses in previously strength-trained women appears greater with a 30-s rest interval between sets compared to longer rest periods of 60- or 120-s.
Eur J Appl Physiol. 2007 Jan 20; [Epub ahead of print] Links
The effect of rest interval length on metabolic responses to the bench press exercise.
* Ratamess NA,
* Falvo MJ,
* Mangine GT,
* Hoffman JR,
* Faigenbaum AD,
* Kang J.
Department of Health and Exercise Science, The College of New Jersey, Ewing, NJ, 08628, USA, ratamess@tcnj.edu.
The purpose of this study was to examine the effects of different rest interval (RI) lengths on metabolic responses to the bench press. Eight resistance-trained men performed 10 randomized protocols [five sets of bench press with 75 or 85% of 1RM for ten (10REP) and five repetitions (5REP), respectively, using different RI (30 s, 1, 2, 3, 5 min)]. Oxygen consumption (VO(2)) was measured during exercise and for 30 min post exercise. For 30-s and 1-min RI: reductions (15-55%) in resistance and volume were observed (set 5 < 4 < 3 < 2 < 1). For 2-min RI: performance was maintained during the first two sets but was reduced by 8-29% during sets 3-5. For 3-min RI: a reduction was observed in volume where sets 4 and 5 were lower than sets 1-3 ( approximately 21%). For 5-min RI: only a reduction in set 5 was observed. Mean VO(2) and ventilation (V (E)) were progressively higher as RI length was shortened. VO(2) area under the curve indicated 10REP > 5REP for all RI except 1-min. Respiratory exchange ratio (RER) was elevated similarly for each protocol. Post exercise, VO(2), V (E), and RER were elevated through 30 min. No differences between RI were observed following 10REP; however, VO(2) after 30-s was higher than 2-, 3-, and 5-min and 1-min was higher than 5-min during 5REP. Fatigue rate was correlated (r = 0.30-0.49) to all metabolic variables. A continuum of performance reductions and metabolic responses were observed. The largest reductions in performance occurred with very short RI (<1 min), and performance was maintained during the first 3-4 sets when 3- and 5-min RI were used.
J Strength Cond Res. 2006 Nov;20(4):978-84.
A brief review: factors affecting the length of the rest interval between
resistance exercise sets.
Willardson JM.
Willardson, J.M. A brief review: Factors affecting the length of the rest
interval between resistance exercise sets. J. Strength Cond. Res. 20(4):978-984.
2006.-Research has indicated that multiple sets are superior to single sets for
maximal strength development. However, whether maximal strength gains are
achieved may depend on the ability to sustain a consistent number of repetitions over consecutive sets. A key factor that determines the ability to sustain repetitions is the length of rest interval between sets. The length of the rest interval is commonly prescribed based on the training goal, but may vary based on several other factors. The purpose of this review was to discuss these factors in the context of different training goals. When training for muscular strength, the magnitude of the load lifted is a key determinant of the rest interval prescribed between sets. For loads less than 90% of 1 repetition maximum, 3-5 minutes rest between sets allows for greater strength increases through the maintenance of training intensity. However, when testing for maximal strength, 1-2 minutes rest between sets might be sufficient between repeated attempts. When training for muscular power, a minimum of 3 minutes rest should be prescribed between sets of repeated maximal effort movements (e.g., plyometric jumps). When training for muscular hypertrophy, consecutive sets should be performed prior to when full recovery has taken place. Shorter rest intervals of 30-60 seconds between sets have been associated with higher acute increases in growth hormone, which may contribute to the hypertrophic effect. When training for muscular endurance, an ideal strategy might be to perform resistance exercises in a circuit, with shorter rest intervals (e.g., 30 seconds) between exercises that involve dissimilar muscle groups, and longer rest intervals (e.g., 3 minutes) between exercises that involve similar muscle groups. In summary, the length of the rest interval between sets is only 1 component of a resistance exercise program directed toward different training goals. Prescribing the appropriate rest interval does not ensure a desired outcome if other components such as intensity and volume are not prescribed appropriately.
(jwbond @ Feb. 18 2008,16:09)</div><div id="QUOTEHEAD">QUOTE</div><div id="QUOTE">Have there ever been any studies with rest periods relation to hypertrophy?</div>
I don't know if these really address your question, Batman, but ....
J Sci Med Sport. 2007 Dec 17 [Epub ahead of print] Links
Effects of rest duration between sets of resistance training on acute hormonal responses in trained women.
Bottaro M, Martins B, Gentil P, Wagner D.
College of Physical Education and Exercise Science, University of Brasilia, Brazil.
This study investigated the acute hormonal response to three different rest periods between sets of a traditional lower body resistance training session in young women. Twelve healthy trained females (26.83+/-3.93 years) participated in the study. On three separate sessions of a lower body resistance exercise protocol, subjects were assigned in a random order a rest interval of 30s (P30), 60s (P60) or 120s (P120) between sets. The resistance exercise session consisted of four lower body exercises with three sets performed until contractile failure using 10-repetition maximum (RM) load. Blood samples were drawn for determination of serum growth hormone (GH) and cortisol concentrations before exercise (T0), immediately after each training session (T1), and after 5min (T5), 15min (T15), and 30min (T30) of recovery. Statistical evaluation of the area under the time-concentration relationship for GH (GHauc) and for cortisol (Cauc) were analyzed using a one-way ANOVA There were no differences among protocols (P30, P60 and P120) in the serum GH and cortisol concentrations at baseline (T0). However, as compared to T0, all protocols led to acute increases (p<0.05) in serum GH concentrations after each training session. The GHauc was greater for P30 than for both P60 and P120, however, there were no differences between P60 and P120. The Cauc were not different among protocols. Thus, the magnitude of acute GH responses in previously strength-trained women appears greater with a 30-s rest interval between sets compared to longer rest periods of 60- or 120-s.
Eur J Appl Physiol. 2007 Jan 20; [Epub ahead of print] Links
The effect of rest interval length on metabolic responses to the bench press exercise.
* Ratamess NA,
* Falvo MJ,
* Mangine GT,
* Hoffman JR,
* Faigenbaum AD,
* Kang J.
Department of Health and Exercise Science, The College of New Jersey, Ewing, NJ, 08628, USA, ratamess@tcnj.edu.
The purpose of this study was to examine the effects of different rest interval (RI) lengths on metabolic responses to the bench press. Eight resistance-trained men performed 10 randomized protocols [five sets of bench press with 75 or 85% of 1RM for ten (10REP) and five repetitions (5REP), respectively, using different RI (30 s, 1, 2, 3, 5 min)]. Oxygen consumption (VO(2)) was measured during exercise and for 30 min post exercise. For 30-s and 1-min RI: reductions (15-55%) in resistance and volume were observed (set 5 < 4 < 3 < 2 < 1). For 2-min RI: performance was maintained during the first two sets but was reduced by 8-29% during sets 3-5. For 3-min RI: a reduction was observed in volume where sets 4 and 5 were lower than sets 1-3 ( approximately 21%). For 5-min RI: only a reduction in set 5 was observed. Mean VO(2) and ventilation (V (E)) were progressively higher as RI length was shortened. VO(2) area under the curve indicated 10REP > 5REP for all RI except 1-min. Respiratory exchange ratio (RER) was elevated similarly for each protocol. Post exercise, VO(2), V (E), and RER were elevated through 30 min. No differences between RI were observed following 10REP; however, VO(2) after 30-s was higher than 2-, 3-, and 5-min and 1-min was higher than 5-min during 5REP. Fatigue rate was correlated (r = 0.30-0.49) to all metabolic variables. A continuum of performance reductions and metabolic responses were observed. The largest reductions in performance occurred with very short RI (<1 min), and performance was maintained during the first 3-4 sets when 3- and 5-min RI were used.
J Strength Cond Res. 2006 Nov;20(4):978-84.
A brief review: factors affecting the length of the rest interval between
resistance exercise sets.
Willardson JM.
Willardson, J.M. A brief review: Factors affecting the length of the rest
interval between resistance exercise sets. J. Strength Cond. Res. 20(4):978-984.
2006.-Research has indicated that multiple sets are superior to single sets for
maximal strength development. However, whether maximal strength gains are
achieved may depend on the ability to sustain a consistent number of repetitions over consecutive sets. A key factor that determines the ability to sustain repetitions is the length of rest interval between sets. The length of the rest interval is commonly prescribed based on the training goal, but may vary based on several other factors. The purpose of this review was to discuss these factors in the context of different training goals. When training for muscular strength, the magnitude of the load lifted is a key determinant of the rest interval prescribed between sets. For loads less than 90% of 1 repetition maximum, 3-5 minutes rest between sets allows for greater strength increases through the maintenance of training intensity. However, when testing for maximal strength, 1-2 minutes rest between sets might be sufficient between repeated attempts. When training for muscular power, a minimum of 3 minutes rest should be prescribed between sets of repeated maximal effort movements (e.g., plyometric jumps). When training for muscular hypertrophy, consecutive sets should be performed prior to when full recovery has taken place. Shorter rest intervals of 30-60 seconds between sets have been associated with higher acute increases in growth hormone, which may contribute to the hypertrophic effect. When training for muscular endurance, an ideal strategy might be to perform resistance exercises in a circuit, with shorter rest intervals (e.g., 30 seconds) between exercises that involve dissimilar muscle groups, and longer rest intervals (e.g., 3 minutes) between exercises that involve similar muscle groups. In summary, the length of the rest interval between sets is only 1 component of a resistance exercise program directed toward different training goals. Prescribing the appropriate rest interval does not ensure a desired outcome if other components such as intensity and volume are not prescribed appropriately.
