Girth measurements, or circumference measurements, are a simple method for tracking changes in body composition, size, and fat distribution over time. This technique provides valuable information for monitoring progress toward fitness goals, assessing muscle development, and tracking changes related to health. Body circumference measures offer a cost-effective, non-invasive way to gauge body changes without requiring expensive or specialized equipment. While not a substitute for clinical body composition analysis, these measurements serve as a practical, easily repeatable tool for health and fitness monitoring.
Establishing Measurement Consistency
To ensure that girth measurements are reliable and comparable across sessions, the technique must be highly consistent. Use a non-stretchable, flexible tape measure, often made of cloth or plastic, to maintain accuracy. When wrapping the tape around the body, it should be snug against the skin but not so tight that it compresses the underlying soft tissues.
The tape must be kept horizontal and parallel to the floor at the measurement site. Maintaining a consistent body posture, usually standing upright with muscles relaxed and weight evenly distributed, is necessary for reliable data. Measurements should ideally be taken at the same time of day, such as in the morning, to minimize natural fluctuations caused by factors like food intake or fluid retention.
Core Trunk Measurements for Health Tracking
The most significant girth measurements for assessing health risk are the waist and hips. Accumulation of fat in the midsection, known as central adiposity, is correlated with increased risk for cardiovascular disease and diabetes. Precise anatomical landmarks are important for accurate health tracking.
Waist Circumference
The waist circumference measurement is used to estimate abdominal fat stores, and has a few accepted standards for its location. One common approach is to measure at the narrowest point of the torso, located between the lower rib margin and the top of the hip bone, or iliac crest. For standardized health assessments, the measurement is taken at the midpoint between the lowest rib and the superior border of the iliac crest. The measurement must be taken horizontally at the end of a normal, relaxed exhale.
Hip Circumference
The hip or gluteal circumference is measured at the maximum horizontal distance around the buttocks. This point usually corresponds to the level of the greater trochanters, which are the prominent bony points at the top of the femur. The combination of the waist and hip measurements is used to calculate the waist-to-hip ratio, an indicator that helps predict cardiovascular risk.
Girth Measurements for Limbs
Girth measurements for the limbs are primarily used to monitor changes in muscle size, which can indicate muscle growth or atrophy.
Upper Arm
The upper arm circumference is measured at the midpoint between two bony landmarks: the acromion process (the point of the shoulder) and the olecranon process (the point of the elbow). The arm should be relaxed and hanging straight down during this measurement to ensure consistency.
Thigh
For the thigh, one common method involves measuring the largest circumference between the hip and the knee. A standardized approach is to take the measurement at a fixed distance from a bony landmark, such as 1 inch below the gluteal fold, or at the mid-thigh point. The mid-thigh point is halfway between the hip crease and the top of the kneecap (patella). Consistency in the chosen site is paramount for comparing results over time.
Calf
The calf circumference measures the lower leg’s muscle mass. This measurement is taken at the point of maximum circumference between the ankle and the knee. The subject should stand with weight evenly distributed on both feet, ensuring the tape measure remains perpendicular to the length of the leg.