46 Chapter 3: Weight Management Table 3.2. Physical Activity Level (PAL) Factors Factor Physical Activity Level 10-12 Sedentary 12-14 Lightly active (e.g., 30-60 min. of physical activity per day; 3-4 times a week) 14-16 Moderately active (e.g., 30-60 min. of physical activity per day; 4-6 times a week) 16-18 Very active (e.g., 1-2 hours of physical activity per day; 4-5 times a week) 19-23 Super active (e.g., 2-4 hours of physical activity per day; 5-6 times a week) Using this information, for example, we can determine what the desired daily caloric intake should be for a 165-pound female who is lightly active and has a target (goal) weight of 135 pounds. This equates to a recommended daily intake of between 1,620 - 1,890 calories (i.e., 135 x 12 = 1,620; 135 x 14 = 1,890). It is worth mentioning, that even if your goal is to lose weight, daily caloric intake should never go below 1,800 calories per day for males or 1,200 calories per day for females (Johnson & Morris, 2012). Additionally, Gilbert (2019) recommends that caloric intake should never go below 30 calories per kilogram, or 13.6 calories per pound, of lean body mass - regardless of gender. Going below these recommendations could result in failing to meet the minimum number of calories required by the basal metabolic rate. This will lower basal metabolic rate resulting in a cascade of negative responses including slowed metabolism and altered gastrointestinal (GI) processes. Failing to meet basic energy needs impacts bone health, sex hormones, the cardiovascular system, mood, and virtually every other vital body process. Using our prior example, let’s assume the female subject had an estimated percent body fat of 34% body, which equates to a lean body mass of 109 pounds (i.e., 165 x 0.34 = 56; 165 -56 = 109). So, the calculation for a daily caloric intake of somewhere between 1,620 - 1,890 calories per day is credible as it complies with both of the above recommendations: greater than 1,200 calories per day for females and greater than 13.6 calories per pound of lean body mass (i.e., 109 x 13.6 = 1,482). Effective Weight Loss Strategies In an attempt to lose weight and/or keep it off, many Americans have resorted to using various weight management strategies that have proven to be either unsafe or ineffective (e.g., severe calorie restriction, excessive exercise, weight loss pills and products). Fortunately, there are several weight management strategies that have proven to be both safe and effective (Fahey et al., 2011; Polivy & Herman, 2005; Thygerson & Thygerson, 2016). Some of these strategies include: • Set reasonable and achievable goals (e.g., body weight, caloric intake, exercise requirements) • Maintain a negative energy balance (e.g., 250 calorie deficit + 250 calorie increase in physical activity) • Increase the amount of daily physical activity
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