Novel insights on the bottom–up rise strength transfer: investigating massed vs. distributed exercise training

Background: The purpose of this study is to investigate the Bottom–Up Rise Strength Transfer (BURST) induced by massed vs. distributed-rehabilitative exercise training. Methods: Participants were randomly allocated to one of the 12 weeks massed (MRT) vs. distributed-(DRT) rehabilitative exercise training (performing lower limb proprioceptive, balance, agility, and resistance exercise) group or no-intervention group (Control). The upper and lower limb strength assessment was recorded at baseline (pre), 8 weeks (mid), and 12 weeks (post). Results: The net right hand MVC force increased after 12 weeks of DRT (58.3%). The net left hand MVC force increased after 12 weeks of both DRT and MRT (44.0% & 33.9% respectively). The BURST effect induced by DRT was significantly larger than MRT (in right hand: 45.1% & in left hand 33.4%). Conclusions: This is the first study investigating in a between-subject design the BURST effect of massed vs. distributed-rehabilitative training. The result showed middle-aged women can develop their upper limbs strength by performing both the DRT and MRT in their lower limbs. Lower body distributed resistance training, however, can provide a significantly greater stimulus for increasing the BURST in middle-aged women.