Assessing physical functioning is important. Such simple tests—such as walk, stand, and sit tests—can predict numerous things. “Testing” defines one’s abilities after being given a set of instructions. Racial differences exist and, of course, both genetic and environmental factors play a part in health disparities between ethnies in America. Minorities report lower levels of physical activity (PA) than whites, this—most often—leads to negative outcomes, but due to their (average) physiology, they can get away with doing “less” than other ethnies. In this article, I will look at studies which talk about racial differences in physical functioning, what it means, and what can be done about it.
Racial differences in physical functioning
Racial differences in self-rated health at similar levels of health exist (Spencer et al, 2009). Does being optimistic or pessimistic about health effect one’s outcomes? Using 2,929 HABC (Health, Aging, and Body Composition) participants, Spencer et al (2009) examined the relationship between self-rated health (SRH) and race, while controlling for demographic, psychosocial and physical health factors. They found that whites were 3.7 times more likely than blacks to report good SRH.
Elderly blacks were more likely to be less educated, reported lower satisfaction with social support, and also had lower scores on a physical battery test than whites. Further, black men and women were less likely to report that walking a quarter mile was “easy”, implying that (1) they have no endurance and (2) weak leg muscles.
Blacks were also more likely to report higher personal mastery:
Participants were asked whether they agreed or disagreed with the following statements: “ I often feel helpless in dealing with the problems of life ” and “ I can do just about anything I really set my mind to do, ” with response categories of disagree strongly, disagree somewhat, agree somewhat, and agree strongly. (Spencer et al, 2009: 90)
Blacks were also more likely to report higher BMI and more chronic health conditions than whites. White men, though, were more likely to report higher global pain, but were older than black men in the sample. When whites and blacks of similar physical functioning were compared, whites were more likely to report higher SRH. Health pessimists were found to be at higher risk of poor health.
Vazquez et al (2018) showed that ‘Hispanics’ were less likely to report having mobility limitations than whites and blacks even after adjustment for age, gender, and education. Blacks, compared to non-‘Hispanic’ whites were more likely to have limitations on activities of daily living (ADL) and instrumental activities of daily living (IADL) For ADL limitations, questions like “Do participant receive help or supervision with personal care such as bathing, dressing, or getting around the house because of an impairment or a physical or mental health problem?” and for IADLs “Does participant receive help or supervision using the telephone, paying bills, taking medications, preparing light meals, doing laundry, or going shopping?” (Vazquez et al, 2018: 4). They also discuss the so-called “Hispanic paradox” (which I discussed), but could not come to a conclusion on the data they acquired. Nonetheless, ‘Hispanic’ participants were less likely to report mobility issues; blacks were more likely than whites to report significant difficulties with normal activities of daily living.
Araujo et al (2010) devised a lower-extremities chair test: how quickly one can stand and sit in a chair; along with a walking test: the time it takes to walk 50 feet. Those who could not complete the chair test were given a score of ‘0’. Overall, the composite physical function (CPF) score for blacks was 3.45, for ‘Hispanics’ it was 3.66, and for whites, it was 4.30. This shows that older whites were stronger—in the devised tests—and that into older age whites are more likely to not need assistance for everyday activities.
This is important because differences in physical functioning between blacks and whites can explain differences in outcomes one year after having a stroke (Roth et al, 2018). This makes sense, knowing what we know about stroke, cognitive ability and exercise into old age.
Shih et al (2005) conclude:
a nationally representative study of the US population, indicate that among older adults with arthritis: (1) racial disparities found in rates of onset of ADL [activities of daily living] limitations are explained by differences in health needs, health behaviors, and economic resources; (2) there are race-specific differences in risk factors for the onset of ADL limitations; and (3) physical limitations are the most important risk factor for onset of ADL limitations in all racial and ethnic groups.
Safo (2012) showed that out of whites, blacks and “Hispanics”, blacks reported the most (low back) pain, worse role functioning score and overall physical functioning score. Lavernia et al (2011) also found that racial/ethnic minorities were more likely to report pain and have lower physical functioning after having a total knee arthroplasty (TKA) and total hip arthroplasty (THA). They found that blacks and ‘Hispanics’ were more likely to report pain, decreased well-being, and have a lower physical functioning score, which was magnified specifically in blacks. Blacks were more likely to report higher levels of pain than whites (Edwards et al, 2001; Campbell and Edwards, 2013), while Kim et al (2017) showed that blacks had lower pain tolerance and higher pain ratings. (Read Pain and Ethnicity by Ronald Wyatt.)
Sarcopenia is the loss of muscle tissue which is a natural part of the aging process. Sarcopenia—and sarcopenic obesity (obesity brought on by muscle loss due to aging)—shows racial/ethnic/gender differences, too. “Hispanics” were the most likely to have sarcopenia and sarcopenic obesity and blacks were least likely to acquire those two maladies (Du et al, 2018). They explain why sarcopenic obesity may be higher in ‘Hispanic’ populations:
One possibility to explain the higher rates of sarcopenia and SO in the Hispanic population could be the higher prevalence of poorly controlled chronic disease, particularly diabetes, and other health conditions.
We were surprised to find that Hispanic adults had higher rates of sarcopenia and SO [sarcopenic obesity]. One possible explanation could be the disparity in mortality rates among ethnic populations. Populations that have greater survival rates may live longer even with poorer health and thus have greater chance of developing sarcopenia. Alternatively, populations which have lower survival rates may not live long enough to develop sarcopenia and thus may identify with lower prevalence of sarcopenia. This explanation appears to be supported by the results of our study and current mortality statistics; NH Blacks have the highest mortality rate, followed by NH Whites, and lastly Hispanics.
Differences in physical activity could, of course, lead to differences in sarcopenic obesity. Physical activity leads to an increase in testosterone in lifelong sedentary men (Hayes et al, 2017), while those who had high physical activity compared to low physical activity were more likely to have high testosterone, which was not observed between the groups that were on a calorie-restricted diet (Kumagai et al, 2016). Kumagai et al (2018) also showed that vigorous physical exercise leads to increases in testosterone in obese men:
We demonstrated that a 12-week aerobic exercise intervention increased serum total testosterone, free testosterone, and bioavailable testosterone levels in overweight/obese men. We suggest that an increase in vigorous physical activity increased circulating testosterone levels in overweight/obese men.
(Though see Hawkins et al, 2008 who show that only SHGB and DHT increased with no increase in testosterone.)
So, clearly, since exercise can increase testosterone levels in obese subjects, and higher levels of testosterone are associated with lower levels of adipose tissue; since adequate levels of steroid hormones are needed for lower levels of adipose tissue (Mammi et al, 2012), then since exercise increases testosterone and higher levels of testosterone lead to lower levels of adipose tissue, if physical activity is increased, then levels of obesity and sarcopenic obesity should decrease in those populations.
Racial differences in physical functioning exist; these differences in physical functioning that exist have grave consequences for certain events, especially after a stroke. Differences in physical functioning/activity cause differences in sarcopenia/sarcopenic obesity in different ethnies. This can be ameliorated by targeting at-risk groups with certain outreach. This type of research shows how differences in lifestyle between ethnies cause differences in physical activity between ethnies as the years progress.
(Also read Evolving Human Nutrition: Implications for Public Health, specifically Chapter 8 on socioeconomic status and health disparities for more information on how and why differences like this persist between ethnies in America.)