Heart Rate Variability and Cardiovascular Adaptations Among Cancer-Survivors Following a 26-Week Exercise Intervention.

Cardiotoxicity as a result of cancer treatment contributes to autonomic dysfunction and decreased cardiorespiratory fitness among cancer survivors. These deleterious cardiovascular outcomes reduce the survival prognosis for cancer patients and contribute to poor quality of life among survivors. Exercise interventions have been shown as effective in mitigating treatment-related side effects. However, previously published interventions have not explored the potential for improvement in autonomic dysfunction (heart rate variability, HRV). This study examined cardiovascular adaptations in cancer survivors (n = 76) who participated in a 26-week intervention consisting of combined aerobic and resistance training (CART). The most noteworthy improvements occurred during the first 13 weeks of training and were maintained throughout the end of the 26-week period. HRrest improved from baseline (PRE) to the midpoint (MID) (P = .036) and from PRE to POST timepoints (P = .029). HRV and VO2max did not initially appear to change in response to CART. However, after stratification on time since treatment, participants who were 5 or more years from their last treatment experienced improvements (ie increase) in the HRV characteristic of HF power (P = .050) and also in VO2max (P =.043), when compared to those experiencing less than 5 years of time since their last treatment. These findings highlight a need for more attention to address the cardiorespiratory deficits experienced by those who have recently completed cancer treatment. In conclusion, the CART intervention is effective in improving cardiorespiratory fitness and autonomic dysfunction. The structure of the intervention is feasible for cancer survivors to continue with at home, using minimal resources, and without supervision. This at-home model may be even more acceptable to recent survivors that may be homebound immediately following treatment.

Fall-related Comorbidity and Health Beliefs among Cancer Survivors Participating in a Community-based Exercise Intervention.

OBJECTIVES: Health beliefs (HB) and fall and balance-related outcomes were examined following a 26-week community-based exercise intervention among cancer survivors (CS). METHODS: Fall and balance-related measures and HB were quantitatively and qualitatively examined during a 26-week intervention among CS (N = 33). Of the 33 participants, 28 consented to an interview about their physical activity (PA) behavior. RESULTS: Participants scored high on balance efficacy (median ± range = 8.68 ± 1.53) and reported high perception of having barriers to PA (mean ± SD = 4.66 ± 0.59). Fall-related measures improved after the 26-week intervention (p = .002). Most cues to action to engage in PA were delivered by a healthcare professional (N = 18). Once enrolled in the intervention, social benefits and access to a program tailored toward CS emerged as motivating factors to engage in PA (N = 12, N = 11, respectively). CONCLUSIONS: There is a need to design fall risk reduction programs tailored to CS and to offer these programs in an environment that fits the unique physical and social needs of CS.

Cardiometabolic Health Among Cancer Survivors: A 13-Week Pilot Study of a Combined Aerobic and Resistance Training Program.

PURPOSE/OBJECTIVES: To explore the feasibility of combined aerobic and resistance training (CART) as a safe method of improving cardiometabolic health among cancer survivors.
. DESIGN: Descriptive and longitudinal pilot study for exercise intervention.
. SETTING: University campus in Los Angeles, California.
. SAMPLE: A multiethnic population of cancer survivors (N = 11) was recruited by convenience sampling and physician referral. 
. METHODS: Consenting participants were prescribed CART for one hour per day, three days per week for 13 weeks.
. MAIN RESEARCH VARIABLES: Components of cardiometabolic health were measured, including resting heart rate (HRrest), blood pressure, body mass index, waist circumference, body fat percentage, and android fat percentage at baseline and after 13 weeks of training. Fasting blood glucose, insulin, adiponectin, leptin, tumor necrosis factor alpha, and C-reactive protein (CRP) also were assessed at baseline and after 13 weeks of training.
. FINDINGS: More than half of the participants reported living with at least two other chronic diseases or conditions in addition to a cancer diagnosis. Five of six African American and Hispanic participants reported the presence of at least two risk factors for metabolic syndrome, compared to one of five Caucasian participants. After 13 weeks of training, participants experienced an average decrease in waist circumference. Decrease in waist circumference was associated with a decrease in CRP. A relationship also was suggested between number of exercise sessions attended and improvement in HRrest. 
. CONCLUSIONS: A CART intervention among cancer survivors should continue to be explored in a larger sample to establish efficacy and effectiveness at improving cardiometabolic health. Because of the higher risk of comorbidity among cancer survivors in comparison to cancer-free adults, improving cardiometabolic health is as important as monitoring cancer recurrence. A need exists for increased attention to the post-treatment cardiometabolic health of cancer survivors and also for examining potential cardiometabolic health disparities among non-Caucasian cancer survivors.
. IMPLICATIONS FOR NURSING: CART may be a plausible alternative to reduce the risk of metabolic syndrome and improve cardiometabolic health among cancer survivors. Additional studies that continue to explore the efficacy and effectiveness of CART may provide more information to help nurses and physicians determine whether the cancer survivorship care plan should include an exercise-based alternative to intervene on cardiometabolic health.

Combined aerobic and resistance training improves bone health of female cancer survivors.

INTRODUCTION: Cancer pathogenesis and resulting treatment may lead to bone loss and poor skeletal health in survivorship. The purpose of this investigation was to evaluate the influence of 26 weeks of combined aerobic and resistance-training (CART) exercise on bone mineral density (BMD) in a multi-racial sample of female cancer survivors. METHODS: Twenty-six female cancer survivors volunteered to undergo CART for 1 h/day, 3 days/week, for 26 weeks. The Improving Physical Activity After Cancer Treatment (IMPAACT) Program involves supervised group exercise sessions including 20 min of cardiorespiratory training, 25 min of circuit-style resistance-training, and 15 min of abdominal exercises and stretching. BMD at the spine, hip, and whole body was assessed using dual-energy X-ray absorptiometry (DXA) before and after the intervention. Serum markers of bone metabolism (procollagen-type I N-terminal propeptide, P1NP, and C-terminal telopeptides, CTX) were measured at baseline, 13 weeks, and at study completion. RESULTS: Eighteen participants, with the average age of 63.0 ± 10.3 years, completed the program. Mean duration since completion of cancer treatment was 6.2 ± 10.6 years. Paired t-tests revealed significant improvements in BMD of the spine (0.971 ± 0.218 g/cm2 vs. 0.995 ± 0.218 g/cm2, p = 0.012), hip (0.860 ± 0.184 g/cm2 vs. 0.875 ± 0.191 g/cm2, p = 0.048), and whole body (1.002 ± 0.153 g/cm2 vs. 1.022 ± 0.159 g/cm2, p = 0.002). P1NP declined 22% at 13 weeks and 28% at 26 weeks in comparison to baseline (p < 0.01) while CTX showed a non-significant decrease of 8% and 18% respectively. CONCLUSIONS: We report significant improvements in BMD at the spine, hip, and whole body for female cancer survivors who completed 26 weeks of CART. This investigation demonstrates the possible effectiveness of CART at improving bone health and reducing risk of osteoporosis for women who have completed cancer treatment. The IMPAACT Program appears to be a safe and feasible way for women to improve health after cancer treatment.

Effect of training mode on post-exercise heart rate recovery of trained cyclists.

The sympathetic nervous system dominates the regulation of body functions during exercise. Therefore after exercise, the sympathetic nervous system withdraws and the parasympathetic nervous system helps the body return to a resting state. In the examination of this relationship, the purpose of this study was to compare recovery heart rates (HR) of anaerobically versus aerobically trained cyclists. With all values given as means ± SD, anaerobically trained track cyclists (n=10, age=25.9 ± 6.0 yrs, body mass=82.7 ± 7.1 kg, body fat=10.0 ± 6.3%) and aerobically trained road cyclists (n=15, age=39.9 ± 8.5 yrs, body mass=75.3 ± 9.9 kg, body fat=13.1 ± 4.5%) underwent a maximal oxygen uptake test. Heart rate recovery was examined on a relative basis using heart rate reserve as well as the absolute difference between maximum HR and each of two recovery HRs. The post-exercise change in HR at minute one for the track cyclists and road cyclists respectively were 22 ± 8 bpm and 25 ± 12 bpm. At minute two, the mean drop for track cyclists was significantly (p<0.05) greater than the road cyclists (52 ± 15 bpm and 64 ± 11 bpm). Training mode showed statistically significant effects on the speed of heart rate recovery in trained cyclists. Greater variability in recovery heart rate at minute two versus minute one suggests that the heart rate should be monitored longer than one minute of recovery for a better analysis of post-exercise autonomic shift.