title: Comparison of muscle activity and tissue oxygenation during strength training protocols that differ by their organisation, rest interval between sets, and volume.
abstract: OBJECTIVE
  The acute effects of a single training session on muscle activity and oxygenation were compared between a new strength training method (3/7 protocol) and a more classical method (4 × 6 and 8 × 6 protocols).
  
  
  METHODS
  All protocols consisted of lifting and lowering a load (70 % 1RM) with the elbow-flexor muscles. The 3/7 protocol involved 5 sets of increasing number of repetitions during successive sets (from 3 to 7 repetitions), and brief rest interval between sets (15 s). The other two protocols consisted of either 4 or 8 sets of 6 repetitions with a rest interval between sets of 2.5 min. Surface electromyogram (EMG) of biceps brachii, brachioradialis, and triceps brachii, and tissue oxygenation index (TOI) of the two elbow flexors were recorded.
  
  
  RESULTS
  For all muscles, EMG increased similarly (50-60 %) during each set in the 4 × 6 and 8 × 6 protocols but gradually during the successive sets in the 3/7 protocol. At protocol completion, EMG reached greater value (p < 0.003) in the 3/7 protocol. TOI decreased during each set in all protocols but contrary to 4 × 6 and 8 × 6 protocols, it did not return to resting values between sets in the 3/7 protocol. The deficit in TOI per repetition was greater (p < 0.001) in the 3/7 (-142.5 ± 48.8 %) than 4 × 6 (-113.1 ± 48.8 %) and 8 × 6 (-105.9 ± 59.2 %) protocols for biceps brachii but not brachioradialis.
  
  
  CONCLUSIONS
  The results indicate that brief rest interval between sets and incremental number of repetitions in successive sets induced greater muscle activity and metabolic changes compared with method of constant repetitions per set and longer rest interval.
authors.affiliation: Centre d'Aide à la Performance Sportive (CAPS), CP 640, 808 route de Lennik, 1070, Brussels, Belgium.|Laboratory of Applied Biology and Neurophysiology, Faculty for Motor Sciences, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), 808 route de Lennik, CP 640, 1070, Brussels, Belgium.
authors.forename: Félix
authors.initials: F
authors.lastname: Penzer
authors.affiliation: Laboratory of Applied Biology and Neurophysiology, Faculty for Motor Sciences, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), 808 route de Lennik, CP 640, 1070, Brussels, Belgium.
authors.forename: Alexis
authors.initials: A
authors.lastname: Cabrol
authors.affiliation: Laboratory of Applied Biology and Neurophysiology, Faculty for Motor Sciences, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), 808 route de Lennik, CP 640, 1070, Brussels, Belgium.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Baudry
authors.affiliation: Centre d'Aide à la Performance Sportive (CAPS), CP 640, 808 route de Lennik, 1070, Brussels, Belgium. jduchat@ulb.ac.be.|Laboratory of Applied Biology and Neurophysiology, Faculty for Motor Sciences, ULB Neuroscience Institute, Université libre de Bruxelles (ULB), 808 route de Lennik, CP 640, 1070, Brussels, Belgium. jduchat@ulb.ac.be.
authors.forename: Jacques
authors.initials: J
authors.lastname: Duchateau
mesh_terms: D000328:Adult; D004551:Elbow Joint / Q000502:physiology; D005260:Female; D000072696:High-Intensity Interval Training / Q000379:methods*; D006801:Humans; D017770:Lifting; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption / Q000502:physiology; D064797:Physical Conditioning, Human / Q000379:methods / Q000502:physiology; D055070:Resistance Training / Q000145:classification / Q000379:methods*; D012146:Rest / Q000502:physiology; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: Dynamic contractions; Electromyography; Metabolic stress; Near-infrared spectroscopy; Training methods