Fitness Formulas

1. Body Mass Index (BMI)

Formula: BMI=weight(kg)height2(m2)BMI = \frac{weight (kg)}{height^2 (m^2)}BMI=height2(m2)weight(kg)​

Description: BMI is a widely used method to classify individuals based on their body weight relative to their height. It provides a general indication of whether a person is underweight, normal weight, overweight, or obese.

Tips:

• Use BMI as a general guideline; it doesn't account for muscle mass or fat distribution.

• For more accurate health assessments, combine BMI with other measurements like body fat percentage and waist circumference.

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2. Basal Metabolic Rate (BMR)

Formulas:

• Harris-Benedict Equation (Revised):

  • Men: BMR=88.362+(13.397×weight(kg))+(4.799×height(cm))−(5.677×age(years))BMR = 88.362 + (13.397 \times weight (kg)) + (4.799 \times height (cm)) - (5.677 \times age (years))BMR=88.362+(13.397×weight(kg))+(4.799×height(cm))−(5.677×age(years))

  • Women: BMR=447.593+(9.247×weight(kg))+(3.098×height(cm))−(4.330×age(years))BMR = 447.593 + (9.247 \times weight (kg)) + (3.098 \times height (cm)) - (4.330 \times age (years))BMR=447.593+(9.247×weight(kg))+(3.098×height(cm))−(4.330×age(years))

• Mifflin-St Jeor Equation:

  • Men: BMR=(10×weight(kg))+(6.25×height(cm))−(5×age(years))+5BMR = (10 \times weight (kg)) + (6.25 \times height (cm)) - (5 \times age (years)) + 5BMR=(10×weight(kg))+(6.25×height(cm))−(5×age(years))+5

  • Women: BMR=(10×weight(kg))+(6.25×height(cm))−(5×age(years))−161BMR = (10 \times weight (kg)) + (6.25 \times height (cm)) - (5 \times age (years)) - 161BMR=(10×weight(kg))+(6.25×height(cm))−(5×age(years))−161

Description: BMR represents the number of calories your body needs to maintain basic physiological functions (like breathing and circulation) at rest. It forms the basis for calculating total daily energy expenditure (TDEE).

Tips:

• Use BMR to determine your daily caloric needs.

• Adjust your calorie intake based on your activity level to achieve weight loss, maintenance, or gain goals.

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3. Total Daily Energy Expenditure (TDEE)

Formula: TDEE=BMR×Activity LevelTDEE = BMR \times Activity\ LevelTDEE=BMR×Activity Level

Activity Level Multipliers:

• Sedentary (little or no exercise): BMR×1.2BMR \times 1.2BMR×1.2

• Lightly active (light exercise/sports 1-3 days a week): BMR×1.375BMR \times 1.375BMR×1.375

• Moderately active (moderate exercise/sports 3-5 days a week): BMR×1.55BMR \times 1.55BMR×1.55

• Very active (hard exercise/sports 6-7 days a week): BMR×1.725BMR \times 1.725BMR×1.725

• Super active (very hard exercise/sports and physical job): BMR×1.9BMR \times 1.9BMR×1.9

Description: TDEE estimates the total number of calories you burn in a day, considering both basal metabolic functions and physical activity. It's essential for planning calorie intake for weight management.

Tips:

• Adjust TDEE calculations based on changes in activity level.

• Regularly reassess TDEE as you progress in your fitness journey to ensure your caloric intake aligns with your goals.

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4. Target Heart Rate (THR) for Cardio Training

Formula: THR=Maximum Heart Rate×Desired IntensityTHR = Maximum\ Heart\ Rate \times Desired\ IntensityTHR=Maximum Heart Rate×Desired Intensity

Maximum Heart Rate (MHR): MHR=220−ageMHR = 220 - ageMHR=220−age

Description: THR helps you exercise within a specific heart rate range to maximize cardiovascular benefits. Different intensity levels target various fitness goals, such as fat burning or improving cardiovascular endurance.

Tips:

• Use a heart rate monitor to track your heart rate during exercise.

• Adjust your exercise intensity to stay within your target heart rate zone for optimal benefits.

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5. One-Rep Max (1RM)

Formula: 1RM=weight×(1+(0.0333×reps))11RM = \frac{weight \times (1 + (0.0333 \times reps))}{1}1RM=1weight×(1+(0.0333×reps))​

Description: 1RM is the maximum amount of weight you can lift for one repetition of a given exercise. It's commonly used to assess strength and set appropriate weightlifting goals.

Tips:

• Test your 1RM periodically to measure strength progress.

• Use percentages of your 1RM to structure your weightlifting program (e.g., lifting 70% of your 1RM for multiple reps).

6. Macronutrient Distribution

Formula: Daily Caloric Intake=TDEE\text{Daily Caloric Intake} = \text{TDEE}Daily Caloric Intake=TDEE Protein Calories=Total Calories×Protein Percentage\text{Protein Calories} = \text{Total Calories} \times \text{Protein Percentage}Protein Calories=Total Calories×Protein Percentage Carbohydrate Calories=Total Calories×Carbohydrate Percentage\text{Carbohydrate Calories} = \text{Total Calories} \times \text{Carbohydrate Percentage}Carbohydrate Calories=Total Calories×Carbohydrate Percentage Fat Calories=Total Calories×Fat Percentage\text{Fat Calories} = \text{Total Calories} \times \text{Fat Percentage}Fat Calories=Total Calories×Fat Percentage

Description: Determines the distribution of calories among the three macronutrients: protein, carbohydrates, and fats. Common ratios are 40% carbohydrates, 30% protein, and 30% fat, but these can be adjusted based on individual goals and preferences.

Tips:

• Use a macronutrient calculator to ensure you're meeting your dietary needs.

• Adjust macronutrient ratios based on your fitness goals (e.g., higher protein for muscle gain).

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7. Lean Body Mass (LBM)

Formula: LBM=weight×(100−Body Fat Percentage)100LBM = \frac{weight \times (100 - Body\ Fat\ Percentage)}{100}LBM=100weight×(100−Body Fat Percentage)​

Description: LBM is the weight of everything in your body except fat. It includes muscles, bones, organs, and fluids. Tracking LBM helps assess changes in muscle mass over time.

Tips:

• Use LBM to monitor muscle gain or loss.

• Pair LBM tracking with body fat percentage measurements for a comprehensive view of your body composition.

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These formulas provide valuable insights and help tailor fitness and nutrition plans to individual needs. Regularly updating your calculations and adjusting your plans accordingly will help you stay on track and achieve your fitness goals more effectively.

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