Muscle Mass Calculator

Here is a method for determining human body muscle mass using the anthropometric measures of girth and skinfolds (Martin et al, 1990). The formula was developed from measurements conducted on cadavers. There are many other methods for determining muscle mass, though most require more sophisticated equipment.

How to Use the Muscle Mass Calculator

Follow these simple steps to calculate your muscle mass accurately:

Understanding Your Results

Your muscle mass calculation provides several important metrics for athletic performance assessment. The primary result shows your total muscle mass in kilograms or pounds, representing the actual muscle tissue in your body excluding fat, bones, and organs.

The muscle mass percentage indicates the proportion of your body weight that is muscle tissue. Elite athletes typically maintain 45-50% muscle mass, while recreational athletes range from 35-40%. Your FFMI (Fat-Free Mass Index) provides a height-adjusted measure of muscularity, useful for comparing athletes of different sizes.

The Science Behind the Martin Formula

Purpose: To calculate body muscle mass using simply attained girth and skinfold measurements.

Equipment required: skinfold calipers, girth measurement tape measure, marker pen, calculator.

Procedure: The formula for calculating muscle mass requires six anthropometric measurements. Follow the links for detailed procedures for recording each of these measurements. Height and girths are measured in cm, skinfolds in mm. See the procedures for: height, mid-thigh girth, calf girth, forearm girth, mid-thigh skinfold and calf skinfold. The girth measurements include subcutaneous fat, which is corrected for using the skinfold measures.

Results: The equations to use is as follows, where: H = height, FG = forearm girth, CG = calf girth, CCG = corrected calf girth, TG = mid-thigh girth, CTG = corrected mid-thigh girth, π = Pi.

CTG = TG - π(mid-thigh skinfold/10)
CCG = CG - π(calf skinfold/10)
Muscle mass (g) = H(0.0553CTG² + 0.0987FG² + 0.0331CCG²) - 2445

Sport-Specific Muscle Mass Applications

Powerlifting and Weightlifting

Olympic weightlifters typically maintain muscle mass percentages of 45-50%, with elite performers often exceeding these values. The IPF (International Powerlifting Federation) weight classes correlate strongly with optimal muscle mass ranges. Athletes in the 74kg class typically carry 35-38kg of muscle mass, while super-heavyweights may exceed 60kg of pure muscle tissue.

Bodybuilding and Physique Sports

Competitive bodybuilders achieve extraordinary muscle mass levels, often reaching 50-55% during competition preparation. Natural bodybuilders typically maintain FFMI scores between 22-25, while the theoretical genetic limit is considered around 25-26 without pharmaceutical assistance. Off-season muscle mass monitoring helps optimize bulking and cutting phases.

Team Sports Applications

Rugby forwards require 40-45kg of muscle mass for effective scrummaging, while backs maintain 35-40kg for speed and agility. American football positions show distinct muscle mass profiles: linemen (50-65kg), linebackers (45-50kg), and skill positions (35-45kg). Basketball centers average 45-50kg muscle mass, while guards maintain 35-40kg for optimal court mobility.

Endurance Sports Considerations

Marathon runners typically maintain lower muscle mass (30-35% of body weight) to optimize power-to-weight ratios. Cyclists show sport-specific adaptations with higher lower-body muscle mass (20-25kg legs) relative to upper body. Triathletes balance muscle mass across disciplines, typically maintaining 35-38% total muscle mass.

How to Improve Your Muscle Mass

Building muscle mass requires a systematic approach combining progressive resistance training, adequate protein intake, and sufficient recovery. Research indicates that muscle protein synthesis peaks at 1.6-2.2g of protein per kilogram of body weight for athletes in heavy training.

Training Protocols for Muscle Development

Hypertrophy-focused training typically employs 6-12 repetitions per set at 65-85% of one-repetition maximum. Volume recommendations suggest 10-20 weekly sets per muscle group, adjusted based on training experience and recovery capacity. Compound movements like squats, deadlifts, and bench press should form the foundation, supplemented with isolation exercises for targeted development.

Nutritional Strategies for Muscle Growth

Caloric surplus of 300-500 calories above maintenance supports optimal muscle growth while minimizing fat gain. Distribute protein intake across 4-6 meals, consuming 25-40g per serving to maximize muscle protein synthesis. Pre and post-workout nutrition timing enhances training adaptations, with combined protein and carbohydrate intake showing superior results.

Recovery and Adaptation

Muscle growth occurs during recovery, not training. Aim for 7-9 hours of quality sleep nightly, as growth hormone release peaks during deep sleep phases. Allow 48-72 hours between training the same muscle groups for full recovery. Monitor muscle mass monthly using this calculator to track progress and adjust programming accordingly.

Advantages of the Martin Formula Method

Advantages: This calculation of muscle mass requires equipment that is available in most gyms, compared to many other muscle mass assessment techniques that require expensive and hard to find equipment.

Target population: This formula is applicable for men. This test is suitable for bodybuilders and sports people wanting to monitor changes in body muscle mass with resistance training.

The Martin formula offers several advantages over other muscle mass assessment methods. Unlike DEXA scans or MRI, which cost hundreds of dollars per assessment, anthropometric measurements can be performed repeatedly at minimal cost. The portability of calipers and tape measures allows field testing of entire teams, making it practical for coaches monitoring athlete development throughout a season.

Similar Tests

• Dual-Energy X-Ray Absorptiometry (DEXA) — using this method you can determine body components including non fat soft tissue.
• Total Body Potassium (TBK) accurately determines the body's total cell mass (that is, the active growing tissues in the body), which in turn can be used to estimate fat-free or lean body mass. When this measurement is combined with measurements from the Total Body Protein, you can determine total organ and muscle mass.
• Magnetic Resonance Imaging (MRI) — with MRI it is possible to get accurate measurements of the composition of body tissue, by identifying muscle, fat and organs etc.
• Total Body Electrical Conductivity (TOBEC) — can be used to estimate lean body mass.
• Computed Tomography (CT) — the high quality images can be processed to differentiate and measure the amounts of fat and lean body tissue.