13.4 Nutrition, Metabolism & Energy Expenditure in Rehabilitation

ABPMR Physical Medicine and Rehabilitation Board Exam Study Guide Exam

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1 Chapter 1: Introduction & Exam Overview

1.1 ABPMR Part I Exam Overview & Format 1.2 Board Review Strategy & Content Blueprint Breakdown

2 Chapter 2: Musculoskeletal Medicine

2.1 Shoulder & Upper Extremity Diagnostics 2.2 Knee, Hip & Lower Extremity Conditions 2.3 Spine Pathology, Radiculopathy & Myelopathy 2.4 Inflammatory Arthritis, Tendinopathies & Concussion 2.5 Bone Health, Osteoporosis & Metabolic Bone Disease 2.6 Thoracic Outlet Syndrome & Peripheral Nerve Entrapment 2.7 Fracture Rehabilitation & Immobilization Complications 2.8 Overuse Tendinopathies & Regenerative Medicine 2.9 Gait Analysis & Abnormal Gait Patterns

3 Chapter 3: Spinal Cord Injury Rehabilitation

3.1 ASIA Examination & Impairment Scale 3.2 Spinal Cord Injury Syndromes 3.3 Autonomic Dysreflexia & Acute Complications 3.4 Neurogenic Bladder, Bowel & Secondary Complications

4 Chapter 4: Stroke & Neuromuscular Rehabilitation

4.1 Stroke Vascular Syndromes & Acute Assessment 4.2 Stroke Motor Recovery & Hemiplegic Complications 4.3 Spasticity Assessment & Multimodal Management 4.4 ALS, GBS, CIDP & Neuromuscular Disease Rehab 4.5 Multiple Sclerosis & Demyelinating Disease Rehabilitation 4.6 Parkinsonism, Movement Disorders & Functional Neurologic Disorder

5 Chapter 5: Electrodiagnostics (EMG/NCS)

5.1 Nerve Conduction Studies Principles & Physics 5.2 Needle Electromyography & MUAP Analysis 5.3 Mononeuropathies & Radiculopathy Patterns 5.4 Neuromuscular Junction Disorders & Myopathies

6 Chapter 6: Traumatic Brain Injury

6.1 TBI Severity Classification, Glasgow Coma Scale, and Pathophysiology 6.2 Rancho Los Amigos Levels of Cognitive Functioning and Disability Rating Scale 6.3 Neurobehavioral Sequelae and Agitation Management 6.4 Concussion Evaluation, Vestibular-Ocular Dysfunction, and Return-to-Play/Work Protocols

7 Chapter 7: Chronic Pain & Interventional Spine

7.1 Fluoroscopic Spine Interventions 7.2 Opioid Stewardship & Controlled Substance Compliance 7.3 Complex Regional Pain Syndrome, Fibromyalgia & Myofascial Pain 7.4 Spinal Cord Stimulation & Intrathecal Therapy

8 Chapter 8: Amputee Rehabilitation & Prosthetics

8.1 Amputation Surgical Levels & Medicare K-Levels 8.2 Socket Designs & Suspension Systems 8.3 Prosthetic Feet & Microprocessor Knee Mechanisms 8.4 Post-Amputation Care, Residual Limb & Phantom Pain

9 Chapter 9: Pediatric Rehabilitation

9.1 Cerebral Palsy Classification & GMFCS 9.2 Spina Bifida & Myelomeningocele Management 9.3 Muscular Dystrophies & Neuromuscular Disease in Children 9.4 Pediatric Brachial Plexopathy & Congenital Disorders

10 Chapter 10: Prosthetics, Orthotics & Assistive Technology

10.1 Lower Limb Orthoses — AFOs & KAFOs 10.2 Spinal & Upper Extremity Orthoses 10.3 Upper Limb Prosthetics — Body-Powered vs Myoelectric 10.4 Wheelchairs, Seating Systems & Pressure Mapping

11 Chapter 11: Medical Rehabilitation & Outcomes

11.1 Dysphagia Assessment & Management 11.2 Neurogenic Bladder & Bowel Management 11.3 Pressure Injuries & Wound Management 11.4 Outcome Measures & Medical Complications 11.5 Cancer Rehabilitation & Oncologic Rehabilitation 11.6 Burns, Endocrine/Metabolic & Medical Complications Rehabilitation

12 Chapter 12: Cardiopulmonary Rehabilitation

12.1 Cardiac Rehabilitation Phases & Metabolic Equivalents 12.2 Pulmonary Rehabilitation & COPD Management

13 Chapter 13: Foundational Rehabilitation Concepts

13.1 Kinesiology, Biomechanics & Functional Anatomy 13.2 Rehabilitation Pharmacology & Medication Management 13.3 Research Methodology, Biostatistics & Evidence-Based Practice 13.4 Nutrition, Metabolism & Energy Expenditure in Rehabilitation 13.5 Diagnostic Procedures: Imaging, MSK Ultrasound, Urodynamics & Neuropsych Assessment

13.4 Nutrition, Metabolism & Energy Expenditure in Rehabilitation

Key Takeaways Explain This Topic AI

Adequate calories and protein are essential for wound healing, muscle recovery, and pressure-injury prevention; protein needs rise to ~1.2-1.5 g/kg/day (and higher in burns/wounds), while starvation and immobility drive sarcopenia.

Metabolic equivalents (METs) express energy expenditure: 1 MET ~3.5 mL O2/kg/min (resting metabolic rate); light activity is 1-3 METs, moderate 3-6, and vigorous >6.

Immobility causes a catabolic state—loss of lean mass, negative nitrogen balance, insulin resistance, bone resorption—mitigated by early mobilization, resistance exercise, and adequate nutrition.

Specific populations need attention: dysphagia texture modification, diabetic carbohydrate control, renal protein/phosphorus/potassium limits, and obesity management to offload joints.

Last updated: July 2026

Nutrition, Metabolism & Energy Expenditure in Rehabilitation

Nutrition is a Domain A applied-science topic with direct rehab relevance: wound healing, pressure-injury prevention, muscle recovery, and exercise prescription all depend on substrate availability and energy balance.

Macronutrients & Rehab-Relevant Needs

Nutrient Rehab Need Notes

Protein ~1.0-1.2 g/kg/day baseline; ~1.2-1.5 g/kg/day for wounds/healing; up to ~2 g/kg/day burns Essential for collagen synthesis, immune function, and muscle repair

Calories Meet estimated energy expenditure; avoid both deficit (malnutrition) and excess (obesity) Pressure injury risk rises with malnutrition

• Vitamin C Collagen cross-linking Wound healing
• Zinc Enzyme cofactor, immunity Deficiency impairs healing
• Vitamin A Epithelialization Caution in pregnancy
• Iron / B12 / folate Oxygen transport, anemia Anemia limits exercise tolerance
• Vitamin D / calcium Bone health Immobility, osteoporosis

Hypoalbuminemia and weight loss are screening flags for malnutrition (validate with validated tools—MNA, SGA, SNAQ—and recognize that albumin is a negative acute-phase reactant, not a pure nutrition marker).

• Metabolic Equivalents (METs) 1 MET ~ 3.5 mL O2/kg/min (resting metabolic rate)
• Light: 1-3 METs (slow walking, ADLs)
• Moderate:3-6 METs (brisk walking, cycling, swimming)
• Vigorous:>6 METs (running, competitive sports)

Cardiac and pulmonary rehab use METs to grade exercise intensity and activities; e.g., 6-minute walk, phase II cardiac rehab targets 50-80% of peak capacity. Cardiopulmonary fitness is discussed in Chapter 12; here the unit and its rehab uses are the foundation.

• Immobility-Induced Catabolism Immobility ──► ↓Muscle Protein Synthesis, ↑Protein Breakdown ──► Sarcopenia
• │ ↓Insulin Sensitivity, ↑Bone Resorption
• └── Early Mobilization + Resistance Exercise + Adequate Protein/Nutrition ──► Reverses

Bed rest/immobility rapidly induces negative nitrogen balance, ~1-3% muscle loss per week in older adults, insulin resistance, cardiovascular deconditioning, bone resorption, and pressure-injury risk. Early mobilization, resistance exercise, and adequate protein/calorie intake counteract the catabolic state.

Population-Specific Nutrition

Wound/pressure injury : protein ~1.2-1.5 g/kg/day (higher for severe wounds), vitamins/minerals, hydration; offload and reposition.

Dysphagia : texture-modified diets (IDDSID levels), thickened liquids, supervised feeding, aspiration precautions (see dysphagia section).

Diabetes : carbohydrate consistency, glycemic control (wound healing), avoid hypoglycemia during exercise.

Renal disease : protein tailored to stage, restrict phosphorus/potassium; balance protein needs with renal limits.

Obesity : caloric deficit, behavior change, joint-preserving exercise; reduces load on painful joints.

Burns : hypermetabolic state with very high caloric and protein demand; feeding protocols.

Deconditioning, Obesity, and Energy Balance

Both under-nutrition (sarcopenia, frailty, poor healing) and over-nutrition (obesity, joint load, cardiometabolic risk) impair rehab outcomes. The physiatrist coordinates with dietitians to match intake to expenditure, prioritize protein, and address micronutrient deficits—while exercise prescription (MET-graded) restores cardiovascular and muscular capacity.

Hydration, Wound Healing & Micronutrients

Adequate hydration supports perfusion and wound healing; dehydration and dependent edema both impair tissue oxygenation. Specific micronutrients matter: vitamin C and iron for collagen and oxygen transport, zinc for enzyme function, vitamin A for epithelialization, and the B vitamins for neuropathy (B1, B6, B12). Excess supplementation is not better—e.g., excess vitamin A can impair healing, and zinc excess causes copper deficiency and neuropathy. Targeted repletion of documented deficiencies is the principle.

Sarcopenia, Frailty & the Vicious Cycle

Sarcopenia (age-related muscle loss) and frailty interact with deconditioning and immobility: Sarcopenia/Frailty ──► ↓Activity/Falls ──► Immobility ──► Further Sarcopenia (Cycle)

• │
• └── Resistance Exercise + Adequate Protein + Nutrition + Fall Prevention ──► Reverses

Resistance exercise and adequate protein (with attention to leucine and vitamin D) are the cornerstones of sarcopenia management. Frailty assessment (e.g., Fried criteria, Clinical Frailty Scale) guides prognosis and the aggressiveness of rehabilitation.

Obesity, Energy Balance & Joint Loading

Obesity raises joint reaction forces (especially knee), worsens cardiometabolic risk, complicates transfers and mobility, and is associated with pressure-injury risk in immobile patients. Management combines caloric deficit, behavior change, joint-preserving exercise (aquatic, cycle), and pharmacotherapy/surgery where indicated. Exercise prescription in obesity starts low and progresses gradually, emphasizing adherence and joint protection. The physiatrist balances the dual needs of weight management and strength/mobility restoration.

Hydration, Thermoregulation & Exercise Safety

Thermoregulation matters for rehab safety—older adults and those with autonomic dysfunction (SCI above T6, MS with Uhthoff) have impaired thermoregulation, requiring hydration, cooling, and timing strategies. Cardiac patients (see Chapter 12) require MET-based intensity and symptom/rate monitoring. Across populations, matching intake to expenditure and recognizing deficits (dehydration impairs performance and increases fall risk) completes the energy-expenditure picture the physiatrist manages.