An immobile person is someone who is unable to move or has very limited mobility. This could be due to medical conditions like paralysis, coma, or being bedridden. Even though an immobile person is not active, their body still requires energy and burns calories to sustain basic life functions.
Calorie burning at rest
The number of calories an immobile person burns depends on their basal metabolic rate (BMR). BMR is the amount of energy the body needs for essential processes like breathing, blood circulation, and organ function. It makes up the majority of the calories we burn each day.
BMR is influenced by:
- Age
- Sex
- Body size and composition
On average, adult women have a BMR of 1300-1500 calories per day, while adult men have a BMR of 1600-1800 calories per day. However, BMR can range from as low as 800 calories to as high as 2500 calories depending on the individual.
BMR calculation
BMR can be calculated using the Harris-Benedict equation which takes into account weight, height, age and sex. Here is the Harris-Benedict equation for men and women:
Men: BMR = 88.36 + (13.4 x weight in kg) + (4.8 x height in cm) – (5.7 x age in years)
Women: BMR = 447.6 + (9.2 x weight in kg) + (3.1 x height in cm) – (4.3 x age in years)
For example, a 30-year-old man who is 180 cm tall and weighs 80 kg would have a BMR of:
BMR = 88.36 + (13.4 x 80) + (4.8 x 180) – (5.7 x 30)
= 88.36 + 1072 + 864 – 171
= 1853 calories
So this man’s daily calorie need at rest would be around 1853 calories.
Factors that affect BMR
There are several factors that can affect an immobile person’s BMR and daily calorie needs:
1. Muscle mass
Having more muscle mass increases BMR because muscle tissue is metabolically active. Bedridden individuals are likely to experience muscle wasting over time which lowers BMR.
2. Medical conditions
Certain diseases like cancer, infections, and thyroid disorders can increase BMR. On the other hand, conditions like paralysis and coma may decrease BMR.
3. Medications
Some medications like steroids and epilepsy drugs can boost BMR. Others like beta blockers may cause a dip in BMR.
4. Body temperature
A higher core body temperature, like in the case of a fever, elevates BMR. Lower body temperature in immobile people can reduce BMR.
5. Digestion
The thermic effect of food or energy used to digest meals can account for 5-15% of daily calorie burn. Immobile people who are tube-fed or eat less may see a drop in this number.
6. Brain function
The brain accounts for a major share of resting energy expenditure. Impaired brain function in some immobile people like coma patients can lower BMR.
Calories burned during activities
While an immobile person does not move around to burn calories through exercise, they may engage in minimal activities that burn some additional calories above their BMR. This includes:
Physical therapy
Immobile patients undergoing passive range of motion exercises and physical therapy can burn some extra calories depending on the duration and intensity of therapy. Light therapy may burn up to 200 calories per hour.
Eating
Chewing, swallowing, and digesting food has a thermic effect. The calories burned depend on the size and composition of meals. Eating 3 meals per day could burn around 100-300 calories.
Reading, talking, watching TV
Mental activities like reading, talking, watching TV can burn calories too. About 100 calories may be burnt per hour of non-strenuous mental activity.
Fidgeting
Even small fidgety movements can burn up to 350 calories per day in people who are mostly sedentary.
Calorie needs for weight maintenance
To maintain current weight, immobile people need to consume the same number of calories that their body burns every day. This is made up of:
- BMR calories burnt
- Additional calories for minimal activities
For example, an immobilized 60-year old woman with a BMR of 1300 calories who does 1 hour of light therapy (200 calories) and watches TV for 2 hours (200 calories) will need:
BMR calories: 1300 calories
Therapy calories: 200 calories
TV calories: 200 calories
Total calories needed: 1700 calories
Without enough calories from food intake, an immobile person will lose weight over time. With excess calories, they will gain weight.
Average calorie needs
On average, the estimated daily calorie requirements for immobilized persons are:
| Age Range | Calories Needed |
|---|---|
| 0-2 years | 900-1400 calories |
| 2-3 years | 1200-1400 calories |
| 4-8 years | 1400-1600 calories |
| 9-13 years | 1600-2000 calories |
| 14-18 years | 1800-2400 calories |
| 19-30 years | 1800-2400 calories |
| 31-50 years | 1600-2200 calories |
| 51-70 years | 1400-2000 calories |
| 70+ years | 1300-1800 calories |
However, each person’s needs vary based on their health status, body composition, and specific medical conditions.
Nutrition considerations
Along with calories, getting adequate nutrition is also important for immobilized people. Some key nutrients to focus on include:
Protein
Immobile people need higher protein intake (1.2-1.5 grams/kg body weight) to preserve muscle mass and strength, support healing, and boost immunity.
Vitamin D
Lack of sun exposure can lead to vitamin D deficiency which reduces calcium absorption. Vitamin D is essential for bone health.
Fiber
Constipation is common in immobilized patients. Adequate fiber and fluid intake is necessary for regular bowel movements.
Calcium and vitamin D
These nutrients strengthen bones which become vulnerable when immobilized. Calcium and vitamin D reduce bone loss.
Zinc
Zinc supports wound healing and immunity which may be compromised. It also helps preserve taste sensitivity.
Iron
Iron levels can drop due to lack of activity and appetite. Iron carries oxygen and supports energy levels.
Fluids
Dehydration occurs frequently in bedbound people. Increased fluid intake is vital especially if there is fever, vomiting or diarrhea.
Maintaining healthy weight
Unplanned weight changes are common when mobility is restricted. Gaining or losing too much weight can impact health and quality of life. Some tips to maintain a healthy weight include:
- Get BMR evaluated to estimate calorie needs
- Follow a balanced diet with the right calories and nutrition
- Do muscle-strengthening exercises within ability
- Have small, frequent meals to meet calorie goals
- Keep hydrated and eat fiber-rich foods to manage bowels
- Get early treatment for medical conditions affecting appetite or nutrients
- Have regular weight checks to ensure appropriate intake
When to seek medical advice
It is important to consult a doctor or dietitian in these situations:
- Sudden weight loss or gain of 10% or more in a month
- Very low body weight (BMI less than 18.5)
- Uncontrolled high calorie intake leading to excess weight gain
- Poor intake due to loss of appetite, nausea, swallowing issues
- Specific nutritional deficiencies
- Need for tube feeding or nutrition support
- Special dietary needs due to health conditions
With professional guidance, an appropriate nutrition plan can be made to meet the calorie and nutrient requirements for an immobile person.
Conclusion
The number of calories an immobile person needs varies based on their BMR, activity levels, and health status. On average, between 1300-1800 calories may be required daily for weight maintenance in immobilized adults. Along with calories, adequate intake of nutrients like protein, vitamins, minerals and fluids is also necessary. Monitoring weight, consulting a dietitian and timely treatment of medical issues can help prevent malnutrition in those with restricted mobility.
