HoMedics IB-SC520 Why Should I Monitor My Skeletal Muscle Mass?, Muscle Mass % Ranges †

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Why Is It Important to Monitor Your Total Body Water (TBW%) Percentage?

Monitoring the level of body water can be a useful tool for one’s health maintenance.

Water is an essential component of the body and is one of the body’s overall health indicators. Water makes up approximately 50-70% of the body’s weight and is present proportionally more in lean tissue as compared to fat tissue.

For example:

•73% of lean muscle tissue is water

•80% of blood is water

•25% of fat is water

•22% of bone tissue is water

Additionally, water is also a medium for biochemical reactions that regulate body functions.

The estimated TBW% may vary according to your hydration level. For better accuracy, avoid fluctuations in hydration level prior to taking a measurement.

Why Should I Monitor My Skeletal Muscle Mass?

According to the American College of Sports Medicine (ASCM), lean muscle mass may decrease by nearly 50 percent between the ages of 20 and 90. If you don’t do anything to replace that loss, you’re losing muscle and increasing fat.

It is also important to know your muscle mass during weight reduction. At rest, the body burns approximately 50 additional calories for each pound of muscle gained. Some advantages of gaining muscle mass include:

•Reversing the decline in strength, bone mineral and muscle mass that accompanies age

•Maintenance of flexible joints

•Guide weight reduction when combined with a healthy diet

This body composition scanner tells you the total weight of skeletal muscle in your body. The normal weight of skeletal muscle mass for men is approximately 40% of total body weight. For women, normal muscle mass is approximately 30% of total body weight (International Commission on Radiological Protection, 1975). To find your muscle mass %, follow this formula:

* Muscle Mass (in pounds)

The accuracy of the unit in estimating TBW% will also decrease with individuals suffering

Total Body Weight

= Muscle Mass %

from diseases or illnesses that tend to accumulate water in the body. Please remember that the unit represents only a good approximation of your total body water.

The normal TBW% of an individual varies according to body fat percentage and gender. The table below may be used as a guide:

	Rango de % BF	Rango normal de TBW%
	4 a 14%	70 a 63%
Hombres	15 a 21%	63 a 57%
	22 a 24%	57 a 55%
	25% y m‡s	55 a 37%
	4 a 20%	70 a 58%
Mujeres	21 a 29%	58 a 52%
	30 a 32%	52 a 49%
	33% y m‡s	49 a 37 %

††Source: Derived from Wang & Deurenberg: “Hydration of fat-free body mass”. American Journal Clin Nutr 1999; 69 833-841.

Use the chart below to see if your muscle mass is low, normal or high.

MUSCLE MASS % RANGES †

				Masa Muscular (en libras)
				Normal		Normal
				Mujeres		Hombres
	330	66	83	99	116	132	149	165
	320	64	80	96	112	128	144	160
	310	62	78	93	109	124	140	155
	300	60	75	90	105	120	135	150
	290	58	73	87	102	116	131	145
	280	56	70	84	98	112	126	140
	270	54	68	81	95	108	122	135
	260	52	65	78	91	104	117	130
	250	50	63	75	88	100	113	125
	240	48	60	72	84	96	108	120
	230	46	58	69	81	92	104	115
Peso (en libras)	220	44	55	66	77	88	99	110
	210	42	53	63	74	84	95	105
	200	40	50	60	70	80	90	100
	190	38	48	57	67	76	86	95
	180	36	45	54	63	72	81	90
	170	34	43	51	60	68	77	85
	160	32	40	48	56	64	72	80
	150	30	38	45	53	60	68	75
	140	28	35	42	49	56	63	70
	130	26	33	39	46	52	59	65
	120	24	30	36	42	48	54	60
	110	22	28	33	39	44	50	55
	100	20	25	30	35	40	45	50
		20%	25%	30%	35%	40%	45%	50%
				(%) de Masa Muscular

†Source: HoMedics, 2006. Figures based on the following formula: Weight of individual’s skeletal muscle (in pounds)/total body weight

(in pounds).

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