Skip to main content
AAPM&R 2025 Main banner
JFK
Final Program


Official Program
Icon Legend
This session is not in your schedule.
This session is in your schedule. Click again to remove it.
Presentation Icons
On Demand
On Demand
In-Person
In-Person
Livestream
Livestream
Invite Only
Invite Only
Ticketed
Ticketed
Coffee Break
Coffee Break
Meal
Meal
Reception
Reception
Rate ePoster

Neurological Rehabilitation

Timing and Type of Exercise Influences Systemic Inflammation and Macrophage Activation After Spinal Cord Injury in a Rodent Model

Thursday, October 23, 2025
12:45 PM - 2:15 PM MT
Location: Original Research Theater
Has Audio
Disclosure(s):
Michael Juszczak, MD: No financial relationships to disclose
Kelley Crozier, MBA, MD: No financial relationships to disclose
Background and/or Objectives: Chronic inflammation after spinal cord injury (SCI) is mediated by cytokines that create a pro-inflammatory environment driven by increased macrophage activity. This inflammation contributes to comorbidities like cardiovascular disease, metabolic dysfunction, neurogenic obesity, and neuropathic pain. Prior work shows early exercise can mitigate neuropathic pain and reduce inflammation. This study evaluates how the timing and type of exercise influence systemic inflammation in a rodent SCI model.

Design: randomized controlled animal trial

Setting : university affiliated research lab

Participants : 24 female, Sprague Dawley rats with unilateral C5 spinal cord contusions.

Interventions: Rats were randomized into a naïve control or 3 SCI groups: (1) no exercise, (2) anaerobic wheel running (20 min), or (3) anaerobic resistance (>50 lever pulls at 50g force/session). Exercise was initiated at 5 (early), 12 (intermediate), or 35 (late) days post-injury and performed for 5 days.

Main Outcome Measures: Systemic levels of TNF-α, IL-6, IL-10, and IL-12 via qPCR, and macrophage-driven biomarkers including CD80, iNOS, and ARG1.

Results: Early exercise significantly reduced TNF-α, IL-6, and IL-12 compared to non-exercise controls (p < 0.01), with aerobic exercise yielding greater reductions than anaerobic. Early exercise also reduced CD80 and iNOS, and increased ARG1 (p < 0.05). IL-10 was elevated in the delayed aerobic group versus delayed anaerobic group (p < 0.001).

Conclusions: Early aerobic exercise post-SCI significantly reduces systemic inflammation by lowering pro-inflammatory cytokines and macrophage activation. SCI is a dynamic neuroinflammatory condition, with non-exercised controls showing progressive inflammatory changes. Timing and modality of exercise shape distinct immune responses, underscoring the value of early intervention. Time since injury is critical when prescribing exercise to reduce inflammation. Future studies should explore how exercise type affects muscle phenotype, body composition, and cytokine profiles, and validate findings in human SCI populations.