Wesley D. Dudgeon

Counteracting muscle wasting in HIV-infected individuals

HIV‐infected persons often experience a loss of lean tissue mass, which includes decreases in skeletal muscle mass. This HIV‐associated wasting is significant because it has been associated with accelerated disease progression and increased morbidity. Signalling related to several circulating molecules, including tumour necrosis factor (TNF)‐α, growth hormone, insulin‐like growth factor (IGF)‐1 and testosterone, has been associated with the aetiology of muscle wasting. Additionally, nutritional status related to malnutrition and specific dietary deficiencies may be involved. In an attempt to counter muscle wasting in HIV‐infected persons, treatments have been suggested that target these mechanisms. Nutritional supplementation, cytokine reduction, hormone therapy and resistance exercise training are potential treatments for this condition. Resistance exercise training, which is more easily accessible to this population than other treatments, holds promise in counteracting the process of HIV wasting, as it has been successfully used to increase lean tissue mass in healthy and clinical populations. This review will explore the HIV/AIDS muscle‐wasting syndrome, its aetiology, and the treatments used to counteract wasting.

Physiological and Psychological Effects of Exercise Interventions in HIV Disease

The use of both aerobic and resistance exercise has been shown to improve physiologic parameters such as strength, endurance, time to fatigue, and body composition in the HIV-infected population. Exercise has also been used successfully to treat psychologic conditions such as depression and anxiety that are common in HIV-infected individuals. However, the effects of exercise on immune function in these individuals are uncertain because of conflicting results found among studies. Additionally, many ventures into this area have been attempted with poor research design, resulting in inconclusive evidence or poor generalizability. The focus of this paper is to review the research that has been performed using exercise as an intervention for HIV-infected persons and to determine what needs to be done next to further our understanding of how the HIV-infected body and mind respond to exercise training.

Moderate intensity exercise training reverses functional aerobic impairment in HIV-infected individuals

Abstract HIV infection and HIV drug therapies result in physical and psychological challenges to those living with HIV. These conditions contribute to decreased functional aerobic capacity (FAC). The aim of this study was to determine the effects of a combined moderate-intensity aerobic and resistance exercise intervention on the FAC of HIV-infected individuals. Forty HIV-infected individuals were randomized to an exercise group (EX) who completed six weeks of moderate-intensity exercise training, or to a control group (CON) that did not receive the exercise intervention. Twice weekly, the EX group completed 30 minutes of moderate-intensity aerobic training followed by moderate-intensity resistance training. Prior to, and following, the intervention the FAC for each subject was determined by graded exercise treadmill stress test (GXT). At baseline testing, the mean FAC as determined by treadmill time-based estimation of maximal oxygen consumption was 25% below age-predicted values, a level of reduction indicating the presence of functional aerobic impairment (FAI). Following the intervention, the EX had a significant increase in time to fatigue and estimated VO2 max (p<.001). Further, FAI was eliminated (1% above age predicted values) during the exercise training. The EX group also experienced decreased heart rates during Stages 1 (p=.02), 2 (p=.01), 4 (p=.05) and 6 (p=.02) of the GXT. The CON had no significant changes during the intervention period. These data indicate that six weeks of combined moderate-intensity aerobic and resistance training can improve FAC and eliminate FAI in those with HIV. Results suggest that the functional limitations common in HIV-infected individuals are due in part to detraining that is reversible through moderate exercise adherence.

Physical Activity and Immunity in HIV-Infected Individuals

The purpose of this study was to determine what relationship exists among physical activity levels and viral load and CD4+ cell count in HIV-infected individuals. Increased viral load is associated with disease progression and symptom severity. A convenience sample of 66 male and female subjects between the ages of 18 and 64 years of age (mean 39±8) was recruited from a hospital-based HIV/AIDS clinic. Components of PA were assessed for three continuous days using a mini-motion logger wrist actigraph. These components included mean PA level, and PA index and acceleration index. Pearsons correlational analysis was used to test the strength of association between PA components and viral load or CD4+ cell count. A significant inverse relationship was found between mean PA level and viral load (p=0.047). An inverse relationship was also observed between PA index and viral load (p=0.0061). Neither mean PA nor PA index scores correlated with CD4+ cell counts. Acceleration index, a measure of PA intensity, showed no correlation to viral load or CD4+ cell counts. These findings suggest that increasing levels of physical activity might have beneficial effects on viral load in HIV-infected individuals.

Perceived stress in HIV-infected individuals: Physiological and psychological correlates

Abstract The purpose of this study was to determine the correlation of perceived stress with selected physiological and psychological factors in an HIV-infected, predominantly African American population and to assess the multivariable effects on perceived stress. The variables that correlated significantly with perceived stress were entered into a backward stepwise regression model. Pearsons r analysis showed significant correlations between perceived stress and state and trait anxiety, depression, HIV-related symptoms, sleep quality, daytime sleepiness and fatigue. State and trait anxiety, depression and fatigue retained significance (p<0.1) in the final regression model. These factors explained approximately 80% of the variance in perceived stress. The significant interactions of multiple physiological and psychological correlates suggest that perceived stress is a complex outcome with a multifactorial etiology. Further, the model suggests that psychological factors may contribute to perceived stress in this population more than physiological factors such as HIV-related symptomatology or stage of disease.

Physiological and Psychological Correlates of Sleep in HIV Infection

Insomnia, a common problem associated with HIV disease, is most likely caused by a multitude of factors. This study investigated the correlations between a selected group of physiological and psychological factors and sleep quality in an HIV-infected population. A convenience sample of 79 ethnically diverse HIV-positive adults, ages 24 to 63, completed a number of questionnaires and released their laboratory records for CD4+ cell count and viral load information. Variables significantly related to sleep quality were HIV-related symptoms, total pain, fatigue, depression, state anxiety, and the number of adults in the household. Findings support the need for health care providers to consider factors that contribute to impaired sleep when developing effective care for HIV-infected individuals with sleep disturbance.

Impact of Aerobic and Resistance Exercise on the Health of HIV-Infected Persons

Individuals infected with HIV experience numerous comorbidities caused by the disease progression and medications, lack of (or inability to perform) physical activity, malnutrition, or a combination of these causes. Common symptoms include loss of muscle mass, fatigue, lypodystrophy, lypoatrophy, and decreases in strength, functional capacity, and overall quality of life. Studies have shown that exercise is a potential treatment of many of these symptoms. Research suggests that exercise may produce beneficial physiological changes in the HIV-infected population such as improved body composition and increases in both strength and endurance. In addition, psychological conditions such as depression and anxiety have been shown to be positively affected by exercise. The purpose of this review is to examine the literature regarding effects of aerobic, resistance, and combined aerobic and resistance exercise training on HIV-infected individuals.

Sleep quality and health-related quality of life in HIV-infected African-American women of childbearing age

A descriptive, correlational design was used to examine the associations of sleep quality and stage of illness with health-related quality of life (HRQOL) in HIV-infected African-American women. Participants were recruited from 12 health clinics and AIDS service organizations (ASO) in Georgia, North Carolina, and South Carolina. The sample consisted of 144 African-American women who ranged in age from 20 to 48 years (m=34.8, SD=6.8). The Pittsburgh Sleep Quality Index (PSQI) and the Medical Outcomes Short-Form Health Survey (SF-36) were administered. Participants were categorized as good sleepers (PSQI global score ≥7) or poor sleepers (PSQI global score ≥ 7) using the median global sleep quality score. Differences in HRQOL between good and poor sleepers, as measured by the SF-36, were tested using MANOVA. Good sleepers scored significantly higher (p < 0.0001) for each SF-36 quality of life dimension and the mental and physical health summary scores. Multiple regression analysis indicated that sleep quality is associated with HRQOL, independent of the individual’s stage of illness, more so with mental HRQOL than with physical HRQOL. The results suggest that treatment for poor sleep quality should be a primary concern for the treatment of HIV infection and a means for improving HRQOL.

The Effects of Mouthpiece Use on Cortisol Levels During an Intense Bout of Resistance Exercise

Garner, DP, Dudgeon, WD, and McDivitt, EJ. The effects of mouthpiece use on cortisol levels during an intense bout of resistance exercise. J Strength Cond Res 25(10): 2866–2871, 2011—Research has suggested mouthpiece use during exercise results in an increase in muscle strength and endurance. However, the research is difficult to replicate, and the methodology suggested measures that were too subjective to determine a mouthpiece effect. Thus, the purpose of this study was to use an objective measure to determine a possible physiological mechanism occurring during and after exercise with mouthpiece use. A within-subjects design was used in which 28 division I football players, aged 18–22 years, performed 2 identical bouts of a 1-hour intense resistance exercise, with each subject being randomly assigned the use of a custom-fit mouthpiece either during the first or second session. During both exercise sessions, saliva was analyzed for cortisol at the following time points: pre-exercise, 25, 45, and 60 minutes of exercise, and 10 minutes postexercise. The results revealed a significant difference in cortisol levels with the use of a mouthpiece vs. no mouthpiece (p = 0.019) at 10 minutes postexercise. Additionally, although the expected increase in cortisol levels from pre to 10 minutes postexercise was present in the no-mouthpiece group (p = 0.01), no such increase was observed in the mouthpiece group. These observations are most likely because of the decrease in cortisol from post to 10 minutes post (p = 0.04) in the mouthpiece group. These data demonstrate that although cortisol continued to increase in the no-mouthpiece session, there was a significant decrease in cortisol in the no-mouthpiece condition 10 minutes postexercise.

Aerobic and resistance training improves mood state among adults living with HIV.

The purpose of this investigation was to examine the effects of combined aerobic and resistance exercise training among self-reported mood disturbances, perceived stress, frequency of self-reported symptoms, and symptom distress in a sample of HIV+ adults. For this purpose, 49 participants were randomly assigned into an exercise (EX) or control (CON) group. Those in the EX group completed 50 min of supervised aerobic and resistance training at a moderate intensity twice a week for 6 weeks. The CON group reported to the university and engaged in sedentary activities. Data were collected at baseline before randomization and 6 weeks post intervention. Measures included the symptom distress scale (SDS), perceived stress scale (PSS), profile of mood states (POMS) total score, and the POMS sub-scale for depression and fatigue. A 2 way ANOVA was used to compare between and within group interactions. The EX group showed a significant decrease in reported depression scores (p=0.03) and total POMS (p=0.003). The CON group reported no change in POMS or SDS, but showed a significant increase in PSS. These findings indicate that combination aerobic and resistance training completed at a moderate intensity at least twice a week provides additional psychological benefits independent of disease status and related symptoms.