For a detailed measurement of muscle growth, use a flexible tape measure that you can buy at a craft store. Get a baseline muscle measurement prior to starting your workout program, so you can easily track your growth. Measure your muscles at the same place and in the same way. For example, if you measure your biceps while it is flexed, continue to measure it in a flexed position. Place the tape measure snugly, but not too tightly, against your skin. Write the measurements in a log book to monitor your muscle growth. You can easily measure your forearms, biceps, neck, quadriceps and calves, but it often helps to ask for a partner's assistance. Measure your muscles every four to six weeks. When you monitor the measurements of your muscles, your abdominal measurement should remain the same or slightly decrease. If it begins to increase, you may be gaining fat -- not muscle -- weight.
Lean Body Mass
A body fat measurement in combination with your body weight gives you an indication as to whether your muscles are growing, which is represented by your lean body mass. Determine your weight from a scale. Calculate your body fat percentage either with the same scale or a handheld electrical impedance device, or have a fitness professional show you how to measure your body fat using calipers. Once you have determined your body fat percentage, multiply your weight by the percentage. For example, if you weigh 180 pounds with a body fat percentage of 25, multiply 180 by 25 percent for a total of 45 pounds of fat. Subtract your fat pounds from your body weight, yielding 180 minus 45 for a total of 135 pounds of lean body mass. When you repeat this process in four to six weeks, if the number of your lean body mass pounds increases, you are making muscle gains and can easily track your progress.
In addition to using a tape measure, or a body fat measurement, you have other ways to measure your muscle growth. This is especially important during the initial weeks of a workout program, when often the inches or fat-free percentages do not dramatically change. As an alternative, keep a record of the amount of weight, the repetitions and the sets of each exercise. If you are gaining weight on a weekly basis, you are building muscle. These results should be noticeable in a mirror or in the way your clothes fit.
If you are not seeing the gains in muscle growth that you desire, consider the amount of rest and recovery time that you build into your routine. Your muscles need at least 48 hours to repair from the breakdown that occurs during strength training. During this recovery time, your cells repair and increase in size. If you do not get adequate rest, you return to the workout with cells that are insufficiently repaired. You won't be able to lift as much weight and your muscle gains will be limited.