Efficacy of Multimodal Training to Alter Bone Mineral Density and Body Compositionin Persons with Spinal Cord Injury: A Case Study.
Todd A. Astorino,1 Kara A. Witzke,1 Eric T. Harness2
Department of Kinesiology, California State University San Marcos,1 Project Walk Spinal Cord
Injury Recovery Center, Carlsbad, CA
ABSTRACTBACKGROUNDRESULTSMETHODS

Change in BMD in response to multi-modal training

AIM

To investigate the effects
of intense multi-modal
training on changes inregional and whole-bodybody composition andbone mineral density in aperson with acute SCI.

Subjects
 21 year-old woman 2 mo post-SCI(ASIA A complete injury at C5).
 She completed 6 mo of training, 2 3 d/wk, 2 - 3 h/d, consisting of: electrical stimulation
 load-bearing exercise
 body weight support treadmill
training
 resistance training
 vibration training Training focused on improving
overall physical function, with80% of training focusing on thetrunk and lower extremities
 Training supervised by certified
personnel with 10 yr of experiencein activity-based training for SCI
Pre-exercise Assessments

Subject provided informed consent
and completed a health-history
questionnaire prior to participation.
Assessment of BMD and BCDXA (GE Lunar Prodigy Advance)
scan was completed at 0 and 6 mo.
BMD assessed at the following
sites: (Shields et al., 2005)
 distal femur (DF) proximal tibia (PT) proximal femur (PF) lumbar spine (L1-L4)
 femoral neck (FN) and greater
trochanter (TR)
 whole bodyBody composition was assessedusing DXA

LBM, BW, and FM
 Regional sites including thelegs, trunk (tr), and arms

15

Percent Change (%)

1. Bone loss at weight-bearing sites ofthe lower extremities is a severe
complication in persons with SCI.
2. Increased fat mass (FM) is typicalin persons with SCI, which
increases risks for chronic diseasein this population.
3. Common modes of rehabilitation
include electrical stimulation, loadbearing, vibration, and body weightsupport treadmill training.
4. Efficacy of training to slow boneloss and deleterious changes inbody composition (BC) in the SCI
is equivocal, with protocols
showing significant preservation, orsmall increases, in BMD
characterized by intense training
volumes (> 4 d/wk, ~ 1 h/d, for atleast 6 mo) rather than less rigoroustraining.
5. It has been reported (Clark et al.,2007) that single-mode exercise
may not elicit the mechanostat
threshold (Frost, 1987) needed forbone to respond to training .
6. No study has examined efficacy ofintense multi-modal training to alter
BC and BMD in persons with SCI.

5-5-15-25

DFPT

leg

RFN

LFN

RTR

LTR spine total

Sites

Change in body composition in response to multi-modal training
Changes in body composition in response to multi-modal training
Percent Change (%)

Approximately 12,000 spinal cord injuries (SCI)
occur annually, with 80 % of injuries occurring in men.
A severe complication of acute SCI is osteoporosis,
which is localized at the proximal tibia and distal femur
that typically receive loading. Bone loss enhances
fracture occurrence at the knee and hip in everyday
activities involving little to no trauma. Because boneloss and subsequent fractures elicit severe clinical,
psychological, and financial complications, earlyintervention to slow rate of bone loss in persons withSCI is essential. Efficacy of exercise training to slow
bone loss or promote new bone formation in thispopulation is equivocal, as many studies have failed toprovide a sufficient ‘mechanostat’ threshold to promotebone growth.
In this study, one subject participated in a preliminary
investigation in which DXA scans were performed atbaseline and after 6 mo to assess bone mineral density(BMD). A 21 year-old woman two months post-SCI(ASIA A complete injury at C5) underwent 6 mo ofintense training 2 – 3 d/wk, 2 – 3 h/d, consisting ofvibration training, body weight support treadmill
training, resistance training, electrical stimulation, andload- bearing exercise. Her training program wasdeveloped and supervised by experienced personnel
certified in activity-based recovery of persons with SCI.
Results demonstrated that distal femur BMD wasincreased by 10 % with training, yet proximal tibia (- 14%) and total body leg BMD (- 10 %) were reduced.
Dramatic losses in BMD were observed for the right/leftfemoral neck (6.8 – 11.4 %) and greater trochanter (19.2– 21.9 %). Body mass was increased by 6.4 kg, with theexcess mass attributed to a 35 % increase in fat mass(FM) and minimal decrement (- 1.5 %) in lean bodymass (LBM). Percent body fat increased from 33.5 –41.2 %, with increased FM revealed in the arms (10 %),legs (27 %), and trunk (52 %). LBM was increased in
the legs (11 %), although attenuated in the arm (- 14 %)and trunk (- 7 %).
Leg LBM is typically decreased soon after SCI, andtotal-body and regional depots of fat mass are typicallyincreased. The observed increase in leg LBM highlights
the benefits of intense, multi-modal training to preserve
muscle mass. The marked bone loss at the hip has
inspired modification of her current training to increaseloading at this site to potentially slow bone loss andreduce fracture risk.

60
50
4030
20
100-10-20

BW%BF LBM FMarmFMleg FMtr LMarm LMleg LMtr

Variables

CONCLUSIONS
1. Increased body mass and FM were evident, although LBM in
the leg was increased in response to 6 mo of rigorous multimodal training.
2. Distal femur BMD was increased in response to training, yetBMD at the hip and proximal femur was reduced.
3. Future long-term studies are needed in larger populations toconfirm this increase in distal femur BMD in persons withacute SCI in response to intense, multi-modal training.