1. Effects of Reducing Resistance, Repetitions, and Frequency of Back-Strengthening Exercise in Healthy Young Women: A Pilot Study 
Michio Hongo, MD, Eiji Itoi, MD, Mehrsheed Sinaki, MD, Yoichi Shimada, MD, Naohisa Miyakoshi, MD, Kyoji Okada, MD 
Archives of Physical Medicine and Rehabilitation 
Volume 86, Issue 7, Pages (July 2005)
DOI: /j.apmr
Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

2. Fig 1
Back-strengthening exercise used by subjects in exercise groups. Backpacks contained weights.
Archives of Physical Medicine and Rehabilitation  , DOI: ( /j.apmr )
Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

3. Fig 2
Change in back extensor strength in the 5 study groups. At 8 weeks, back extensor strength was significantly greater in the STD group than in the WRD and FRD groups. At 12 weeks, back extensor strength was significantly greater in the RRD and STD groups than in the controls (CON). Values are mean ± SD.
Archives of Physical Medicine and Rehabilitation  , DOI: ( /j.apmr )
Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions

4. Fig 3
Percentage change in back extensor strength in the 5 study groups. Back extensor strength at 12 weeks was most increased in the STD group (39%), followed by the FRD (25%), WRD (22%), RRD (20%), and control (5%) groups. Percentage change in back extensor strength was significantly greater in the STD group than in any group other than the FRD group. Values are mean ± SD.
Archives of Physical Medicine and Rehabilitation  , DOI: ( /j.apmr )
Copyright © 2005 American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation Terms and Conditions