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    Kristin Campbell

    Muscular strength is a key parameter of rehabilitation programs and a strong predictor of functional capacity. Traditional methods to measure strength, such as manual muscle testing (MMT) and hand-held dynamometry (HHD), are limited by... more
    Muscular strength is a key parameter of rehabilitation programs and a strong predictor of functional capacity. Traditional methods to measure strength, such as manual muscle testing (MMT) and hand-held dynamometry (HHD), are limited by the strength and experience of the tester. The Performance Recorder 1 (PR1) is a strength assessment tool attached to resistance training equipment and may be a time- and cost-effective tool to measure strength in clinical practice that overcomes some limitations of MMT and HHD. However, reliability and validity of the PR1 have not been reported. Test-retest and inter-rater reliability was assessed using the PR1 in healthy adults (n  =  15) during isometric knee flexion and extension. Criterion-related validity was assessed through comparison of values obtained from the PR1 and Biodex® isokinetic dynamometer. Test-retest reliability was excellent for peak knee flexion (intra-class correlation coefficient [ICC] of 0.96, 95% CI: 0.85, 0.99) and knee extension (ICC  =  0.96, 95% CI: 0.87, 0.99). Inter-rater reliability was also excellent for peak knee flexion (ICC  =  0.95, 95% CI: 0.85, 0.99) and peak knee extension (ICC  =  0.97, 95% CI: 0.91, 0.99). Validity was moderate for peak knee flexion (ICC  =  0.75, 95% CI: 0.38, 0.92) but poor for peak knee extension (ICC  =  0.37, 95% CI: 0, 0.73). The PR1 provides a reliable measure of isometric knee flexor and extensor strength in healthy adults that could be used in the clinical setting, but absolute values may not be comparable to strength assessment by gold-standard measures.
    Exercise plays an important role in cancer rehabilitation, but a precise prescription of exercise intensity is required to maximize the benefits of this intervention. It is unknown whether different methods of prescribing aerobic exercise... more
    Exercise plays an important role in cancer rehabilitation, but a precise prescription of exercise intensity is required to maximize the benefits of this intervention. It is unknown whether different methods of prescribing aerobic exercise intensity achieve the same intensity. Breast cancer treatments may alter exercise response and thereby may affect the accuracy of these methods. The purpose of this study was to compare the accuracy and achieved intensity of four common methods of prescribing exercise intensity within and between breast cancer patients recently finished chemotherapy (n = 10), survivors finished treatment (n = 10), and healthy controls (n = 10). The methods compared were as follows: the American College of Sports Medicine's metabolic equation for treadmill walking (METW), heart rate reserve (HRR), direct heart rate (DIRECT HR), and RPE. The methods were used to prescribe 60% oxygen consumption reserve (VO2R) in four randomly assigned 10-min periods of treadmill walking with expired gas collection to evaluate 1) achieved intensity (measured % VO2R) and 2) accuracy (defined as: [60% VO2R-achieved intensity]). The accuracy of the methods was not equivalent across groups (P = 0.04). HRR and METW did not differ across groups and were most accurate in patients. HRR, METW, and DIRECT HR were all more accurate than RPE in survivors (P ≤ 0.01). RPE was the least accurate in all groups. The accuracy of DIRECT HR was much lower in patients than that in survivors and controls (P ≤ 0.01). The four methods of exercise intensity prescription varied in accuracy in prescribing 60% VO2R and did not achieve equivalent exercise intensities within breast cancer patients, survivors, and healthy controls. HRR and METW were the most accurate methods for exercise intensity prescription in breast cancer patients and survivors.
    Assessment of physical fitness is important in order to set goals, appropriately prescribe exercise, and monitor change over time. This study aimed to determine the utility of a standardized physical fitness assessment for use in... more
    Assessment of physical fitness is important in order to set goals, appropriately prescribe exercise, and monitor change over time. This study aimed to determine the utility of a standardized physical fitness assessment for use in cancer-specific, community-based exercise programs. Tests anticipated to be feasible and suitable for a community setting and a wide range of ages and physical function were chosen to measure body composition, aerobic fitness, strength, flexibility, and balance. Cancer Exercise Trainers/Specialists at cancer-specific, community-based exercise programs assessed new clients (n = 60) at enrollment, designed individualized exercise programs, and then performed a re-assessment 3-6 months later (n = 34). Resting heart rate, blood pressure, body mass index, waist circumference, handgrip strength, chair stands, sit-and-reach, back scratch, single-leg standing, and timed up-and-go tests were considered suitable and feasible tests/measures, as they were performed in most (≥88 %) participants. The ability to capture change was also noted for resting blood pressure (-7/-5 mmHg, p = 0.02), chair stands (+4, p < 0.01), handgrip strength (+2 kg, p < 0.01), and sit-and-reach (+3 cm, p = 0.03). While the submaximal treadmill test captured a meaningful improvement in aerobic fitness (+62 s, p = 0.17), it was not completed in 33 % of participants. Change in mobility, using the timed up-and-go was nominal and was not performed in 27 %. Submaximal treadmill testing, handgrip dynamometry, chair stands, and sit-and-reach tests were feasible, suitable, and provided meaningful physical fitness information in a cancer-specific, community-based, exercise program setting. However, a shorter treadmill protocol and more sensitive balance and upper body flexibility tests should be investigated.
    To determine the feasibility of implementing a large-scale primary care-based diabetes prevention trial. A feasibility cluster randomized controlled trial was conducted in British Columbia, Canada, amongst adults with prediabetes using... more
    To determine the feasibility of implementing a large-scale primary care-based diabetes prevention trial. A feasibility cluster randomized controlled trial was conducted in British Columbia, Canada, amongst adults with prediabetes using the Facilitated Lifestyle Intervention Prescription (FLIP) vs. usual care. FLIP included lifestyle advice, a pedometer, and telephone support from a lifestyle facilitator for 6 months. Indicators of feasibility included recruitment rates of family practices, participants and facilitators, as well as feasibility and retention rates in the FLIP program and study protocols. Six family practices participated; 59 patients were enrolled between October 2012 and March 2013. The trial protocol was acceptable to practices and participants and had a 95% participant retention rate over the 6 months (56/59). Adherence to the intervention was high (97%), with 34 of 35 patients continuing to receive telephone calls from the facilitator for 6 months. The mean cost of the intervention was C$144 per person. Compared with control, intervention participants significantly reduced weight by 3.2 kg (95% CI, 1.7 to 4.6); body mass index by 1.2 (95% CI, 0.7 to 1.7) and waist circumference by 3 cm (95% CI, 0.3 to 5.7). It is feasible to implement FLIP and to conduct a trial to assess effectiveness. A larger trial with longer follow up to assess progression to diabetes is warranted.
    Significant arm morbidity is reported following surgery for breast cancer, yet physiotherapy is not commonly part of usual care. This study compared the effect on arm morbidity after surgery for breast cancer of a clinical care pathway... more
    Significant arm morbidity is reported following surgery for breast cancer, yet physiotherapy is not commonly part of usual care. This study compared the effect on arm morbidity after surgery for breast cancer of a clinical care pathway including preoperative education, prospective monitoring, and early physiotherapy (experimental group) to that of preoperative education alone (comparison group). A prospective quasi-experimental pretest-posttest, non-equivalent group design compared two clinical sites; Site A (n=41) received the experimental intervention, and Site B (n=31) received the comparison intervention. At baseline (preoperative) and 7 months postoperative, shoulder range of motion (ROM), upper-extremity (UE) strength, UE circumference, pain, UE function, and quality of life were assessed. The experimental group maintained shoulder flexion ROM at 7 months, whereas the comparison group saw a decrease (mean 1° [SD 9°] vs. -6° [SD 15°], p=0.03). A lower incidence of arm morbidity and better quality of life were observed in the experimental group, but these findings were not statistically significant. Baseline characteristics and surgical approaches differed between the two sites, which may have had an impact on the findings. Initial results are promising and support the feasibility of integrating a surveillance approach into follow-up care. This pilot study provides the foundation for a larger, more definitive trial.
    Randomised controlled trials (RCTs) can evaluate how well a particular exercise programme reduces cancer treatment-related side effects. Adequate design and reporting of the exercise prescription employed in RCTs is central to... more
    Randomised controlled trials (RCTs) can evaluate how well a particular exercise programme reduces cancer treatment-related side effects. Adequate design and reporting of the exercise prescription employed in RCTs is central to interpreting study findings and translating effective interventions into practice. Our previous review on the quality and reporting of exercise prescriptions in RCTs in breast cancer survivors revealed several inadequacies. This review similarly evaluates exercise prescriptions used in RCTs in patients with cancers other than the breast. The literature was searched for RCTs in persons diagnosed with a cancer other than breast. Data were extracted to evaluate the attention to the principles of exercise training in the study design and the reporting of and adherence to the exercise prescription used for the intervention. Of the 33 studies reviewed, none attended to all of the exercise training principles. Specificity was applied by 89%, progression by 26%, overload by 37%, initial values by 26%, diminishing returns by 9% and reversibility by 3%. Only 2 of 33 studies (6%) reported both the exercise prescription in full and adherence to each individual component of the prescription. Application of the principles of training in exercise RCTs of non-breast cancer survivors was incomplete and inconsistent. Given these observations, interpretation of findings from the reviewed studies should consider potential shortcomings in intervention design. Though the prescribed exercise programme was often described, adherence to the entire prescription was rarely reported providing a less accurate picture of dose-response and challenges in translating programmes to community settings.
    OBJECTIVES: Research supports the use of exercise to improve quality of life and reduce the side effects of breast cancer treatment, such as fatigue and decreased aerobic capacity. Previously published reviews have focused on reporting... more
    OBJECTIVES: Research supports the use of exercise to improve quality of life and reduce the side effects of breast cancer treatment, such as fatigue and decreased aerobic capacity. Previously published reviews have focused on reporting the outcomes of exercise interventions, but have not critically examined the exercise prescriptions. The purpose of this review is to evaluate the application of the principles of exercise training in the exercise prescriptions reported in intervention studies for breast cancer survivors. METHODS: Databases were searched for randomised controlled trials of exercise in women diagnosed with breast cancer. Data were extracted to evaluate the application of the principles of exercise training, the reporting of the components of the exercise prescription and the reporting of adherence to the exercise prescription. RESULTS: Of the 29 papers included, none applied all principles of exercise training. Specificity was applied by 64%, progression by 41%, overlo...
    Observational research suggests that exercise may reduce the risk of breast cancer and improve survival. One proposed mechanism for the protective effect of aerobic exercise related to cancer risk and outcomes, but has not been examined... more
    Observational research suggests that exercise may reduce the risk of breast cancer and improve survival. One proposed mechanism for the protective effect of aerobic exercise related to cancer risk and outcomes, but has not been examined definitively, is the immune response to aerobic exercise. Two prevailing paradigms are proposed. The first considers the host immune response as modifiable by aerobic exercise training. This exercise-modulated immune-tumor crosstalk in the mammary microenvironment may alter the balance between tumor initiation and progression versus tumor suppression. The second paradigm considers the beneficial role of exercise-induced, skeletal muscle-derived cytokines, termed "myokines". These myokines exert endocrine-like effects on multiple organs, including the mammary glands. In this systematic review, we i) define the role of macrophages and T-cells in breast cancer initiation and progression; ii) address the two paradigms that support exercise-indu...
    The risk of musculoskeletal injury with the introduction of moderate-to-vigorous exercise in sedentary adults is not well established. The purpose of this report is to examine the effect of a 12-month exercise intervention on... more
    The risk of musculoskeletal injury with the introduction of moderate-to-vigorous exercise in sedentary adults is not well established. The purpose of this report is to examine the effect of a 12-month exercise intervention on musculoskeletal injury and bodily pain in predominately overweight, sedentary men (n = 102) and women (n = 100), ages 40 to 75 years. Participants were randomized to a moderate-to-vigorous aerobic exercise intervention (EX) (6 d/wk, 60 min/d, 60% to 85% max. heart rate) or usual lifestyle control (CON). Participants completed a self-report of musculoskeletal injury and body pain at baseline and 12-months. The number of individuals reporting an injury (CON; 28% vs. EX; 28%, P = .95) did not differ by group. The most commonly injured site was lower leg/ankle/foot. The most common causes of injury were sports/physical activity, home maintenance, or "other." In the control group, bodily pain increased over the 12 months compared with the exercise group (C...
    The International Agency for Research on Cancer estimates that 25% of cancer cases worldwide are caused by overweight or obesity and a sedentary lifestyle. These lifestyle patterns may increase cancer risk by several mechanisms including... more
    The International Agency for Research on Cancer estimates that 25% of cancer cases worldwide are caused by overweight or obesity and a sedentary lifestyle. These lifestyle patterns may increase cancer risk by several mechanisms including increased estrogens and testosterone, hyperinsulinemia and insulin resistance, increased inflammation, and depressed immune function. Several randomized clinical trials have shown that physical activity and diet interventions can change biomarkers of cancer risk. In a controlled physical activity trial, we found decreases in serum estrogen, testosterone, and insulin in overweight, sedentary postmenopausal women with a 1-y exercise program consisting of moderate-intensity aerobic exercise, 45 min/d, 5 d/wk. In another controlled trial in middle-aged to older persons, we found that a 1-y exercise intervention of 60 min/d, 6 d/wk, reduced colon crypt cell proliferation in men who adhered closely to the program. Only 1 trial, the Women's Health Init...
    Physical inactivity and being overweight or obese are lifestyle factors that put breast cancer survivors at a higher risk for a cancer recurrence and/or development of other chronic diseases. Despite this, there is limited research that... more
    Physical inactivity and being overweight or obese are lifestyle factors that put breast cancer survivors at a higher risk for a cancer recurrence and/or development of other chronic diseases. Despite this, there is limited research that has identified effective lifestyle interventions aimed specifically at weight loss in breast cancer survivors. This pilot study is a single-arm experimental pre-post test design, conducted from November 2009 to July 2010, that tested the efficacy of a 24-week group-based lifestyle intervention modeled on the Diabetes Prevention Program in early stage breast cancer survivors (N=14). The intervention included 16 diet sessions led by a registered dietitian and 150 min/wk of moderate-to-vigorous exercise. Study outcome measures were completed at baseline, 24, and 36 weeks (nonintervention follow-up). The primary outcome was change in body weight, and secondary outcomes were change in body composition, aerobic fitness, dietary intake, and blood biomarkers...
    The objectives of the present study were to evaluate the impact of a single bout of high-intensity aerobic exercise on 1) long-term potentiation (LTP)-like neuroplasticity via response to paired associative stimulation (PAS) and 2) the... more
    The objectives of the present study were to evaluate the impact of a single bout of high-intensity aerobic exercise on 1) long-term potentiation (LTP)-like neuroplasticity via response to paired associative stimulation (PAS) and 2) the temporal and spatial components of sequence-specific implicit motor learning. Additionally, relationships between exercise-induced increases in systemic brain-derived neurotrophic factor (BDNF) and response to PAS and motor learning were evaluated. Sixteen young healthy participants completed six experimental sessions, including the following: 1) rest followed by PAS; 2) aerobic exercise followed by PAS; 3) rest followed by practice of a continuous tracking (CT) task and 4) a no-exercise 24-h retention test; and 5) aerobic exercise followed by CT task practice and 6) a no-exercise 24-h retention test. The CT task included an embedded repeated sequence allowing for evaluation of sequence-specific implicit learning. Slope of motor-evoked potential recru...
    ObjectivesLack of exercise and excess body weight may exacerbate treatment-related declines in quality of life (QoL) in endometrial cancer survivors. The primary purpose of this study was to examine the associations among exercise, body... more
    ObjectivesLack of exercise and excess body weight may exacerbate treatment-related declines in quality of life (QoL) in endometrial cancer survivors. The primary purpose of this study was to examine the associations among exercise, body weight, and QoL in a population-based sample of endometrial cancer survivors.
    Background: Physical exercise has been identified as a po- tential intervention to improve quality of life in women with breast cancer. We sought to summarize the available evi- dence concerning the effects of exercise on breast cancer... more
    Background: Physical exercise has been identified as a po- tential intervention to improve quality of life in women with breast cancer. We sought to summarize the available evi- dence concerning the effects of exercise on breast cancer pa- tients and survivors. Methods: We searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, CINAHL, PsychINFO, CancerLit, PEDro and SportDiscus as
    BACKGROUND: Despite evidence of the benefits of exercise in cancer survivors, exercise participation rates tend to decline after treatments. Few studies have examined the determinants of exercise in less common cancer sites. In this... more
    BACKGROUND: Despite evidence of the benefits of exercise in cancer survivors, exercise participation rates tend to decline after treatments. Few studies have examined the determinants of exercise in less common cancer sites. In this study, we examined medical, demographic, and social cognitive correlates of exercise in endometrial cancer survivors using the Theory of Planned Behavior (TPB). METHODS: A mailed survey
    Fatigue is one of the most commonly reported side effects during treatment for breast cancer and can persist following treatment completion. Cancer-related fatigue after treatment is multifactorial in nature, and one hypothesized... more
    Fatigue is one of the most commonly reported side effects during treatment for breast cancer and can persist following treatment completion. Cancer-related fatigue after treatment is multifactorial in nature, and one hypothesized mechanism is cardiorespiratory and neuromuscular deconditioning. The purpose of this study was to compare cardiorespiratory and neuromuscular function in breast cancer survivors who had completed treatment and met the specified criteria for cancer-related fatigue and a control group of breast cancer survivors without fatigue. Participants in the fatigue (n = 16) and control group (n = 11) performed a maximal exercise test on a cycle ergometer for determination of peak power, power at lactate threshold, and VO(2) peak. Neuromuscular fatigue was induced with a sustained submaximal contraction of the right quadriceps. Central fatigue (failure of voluntary activation) was evaluated using twitch interpolation, and peripheral fatigue was measured with an electrically evoked twitch. Power at lactate threshold was lower in the fatigue group (p = 0.05). There were no differences between groups for power at lactate threshold as percentage of peak power (p = 0.10) or absolute or relative VO(2) peak (p = 0.08 and 0.33, respectively). When adjusted for age, the fatigue group had a lower power at lactate threshold (p = 0.02) and absolute VO(2) peak (p = 0.03). There were no differences between groups in change in any neuromuscular parameters after the muscle-fatiguing protocol. Findings support the hypothesis that cardiorespiratory deconditioning may play a role in the development and persistence of cancer-related fatigue following treatment. Future research into the use of exercise training to reduce cardiorespiratory deconditioning as a treatment for cancer-related fatigue is warranted to confirm these preliminary findings.
    Chronic physical activity may alter estrogen metabolism, a proposed biomarker of breast cancer risk, by causing a shift toward higher 2-OHE1 and lower 16alpha-OHE1 levels. To investigate the association between an objective indicator of... more
    Chronic physical activity may alter estrogen metabolism, a proposed biomarker of breast cancer risk, by causing a shift toward higher 2-OHE1 and lower 16alpha-OHE1 levels. To investigate the association between an objective indicator of chronic exercise, aerobic fitness, and 2-OHE1 and 16alpha-OHE1 in premenopausal women. Women with high aerobic fitness (N=17; VO2max>or=48 mL.kg.min-1) were compared with women with average aerobic fitness (N=13; VO2max<or=40 mL.kg.min-1) in terms of 2-OHE1 and 16alpha-OHE1 profiles. Participants were healthy, regularly menstruating, Caucasian women, aged 20-42 yr, with a normal body mass index (BMI) of 18-24, not using pharmacologic contraceptives. We measured height, weight, sum of four skinfolds, and maximal aerobic fitness (VO2max), using an incremental cycle ergometer test. Urine samples were collected during the follicular and luteal phase of the menstrual cycle. There were no statistically significant differences between average and highly fit women for 2-OHE1, 16alpha-OHE1, or the 2:16alpha-OHE1 ratio in either the follicular or luteal phase. However, the high-fitness group showed a trend toward a higher luteal 2:16alpha-OHE1 (P=0.20). In ancillary analyses, a higher sum of skinfolds was associated with significantly higher luteal 16-OHE1 levels (r=0.39, P=0.03) and lower luteal phase 2:16 OHE ratio (r=-0.41, P=0.02). Higher BMI was associated with lower follicular phase 2-OHE1 (r=-0.37, P=0.04) and lower follicular 2:16 OHE1 ratio (r=-40, P=0.03). This exploratory study is the first to investigate the association between aerobic fitness and estrogen metabolites in premenopausal women using metabolic parameters. We observed no statistically significant association between aerobic fitness and 2-OHE1 and 16alpha-OHE1, but found that body composition was associated with 2-OHE1 and 16alpha-OHE1 levels.
    To investigate the effect of a yearlong moderate-intensity aerobic exercise intervention on C-reactive protein (CRP), serum amyloid A (SAA), and interleukin 6 (IL-6) among overweight or obese postmenopausal women. In a randomized... more
    To investigate the effect of a yearlong moderate-intensity aerobic exercise intervention on C-reactive protein (CRP), serum amyloid A (SAA), and interleukin 6 (IL-6) among overweight or obese postmenopausal women. In a randomized controlled trial, 115 postmenopausal, overweight or obese, sedentary women, aged 50-75 yr were randomized to an aerobic exercise intervention of moderate-intensity (60%-75% observed maximal HR), for > or = 45 min x d(-1), 5 d x wk (n = 53), or to a 1-d x wk(-1) stretching control (n = 62), on an intent-to-treat basis. CRP, SAA, and IL-6 were measured at baseline, at 3 months, and at 12 months. From baseline to 12 months, CRP decreased 10% in exercisers and increased 12% in controls (P = 0.01); no effects were observed for SAA and IL-6. Among participants at baseline who were obese (body mass index (BMI) > or = 30 kg x m(-2)) or had abdominal obesity (waist circumference (WC) > or = 88 cm), exercise resulted in a more pronounced reduction in CRP (BMI > or = 30 kg x m(-2), P = 0.002; WC > or = 88 cm, P < 0.0001), borderline for SAA (BMI…
    Physical activity may reduce many side effects of cancer treatment and may improve survival. The purpose of this analysis was to compare physical activity in cancer patients and survivors to those who have never had cancer and examine... more
    Physical activity may reduce many side effects of cancer treatment and may improve survival. The purpose of this analysis was to compare physical activity in cancer patients and survivors to those who have never had cancer and examine changes between 2005-2006 and 2009-2010. Data were extracted from the 2005-2006 and 2009-2010 Canadian Community Health Survey. Respondents were asked whether they currently have or had cancer in the past and about physical activity. Based on duration and type of reported activity, respondents were classified as inactive, moderately active, or active. Logistic regression was used to assess the relationship between cancer history and physical activity. Differences in physical activity by survey cycle according to cancer status were also examined. After adjustment, respondents with cancer were more likely to be inactive than those who had never had cancer (OR = 1.39, 95 % CI 1.21-1.58, inactive vs. active), while individuals with previous cancer did not differ from population levels. The odds of being moderately active or inactive did not vary over time in those with current or previous cancer; however, respondents who had never had cancer were less likely to be moderately active or inactive in 2009-2010 (OR = 0.94, 95 % CI 0.92-0.96, inactive vs. active). Individuals with cancer are less likely to be active than those who have never had cancer, but those with a history of cancer have similar physical activity levels to population levels. Activity levels in all three groups are much lower than recommended. It is encouraging to note that those with cancer history are not less likely than the general population to be physically active. Individuals with a history of cancer have much to gain from participation in physical activity and health care providers should continue to encourage physical activity in accordance with published guidelines.
    Exercise has gained recognition as an effective supportive care intervention for cancer survivors, yet participation rates are low. Knowledge of the specific exercise counseling and programming preferences of cancer survivors may be... more
    Exercise has gained recognition as an effective supportive care intervention for cancer survivors, yet participation rates are low. Knowledge of the specific exercise counseling and programming preferences of cancer survivors may be useful for designing effective interventions. In this study, we examined the exercise preferences of 386 endometrial cancer survivors. Participants completed a questionnaire that included measures of past exercise behavior, exercise preferences, and medical and demographic information. Some key findings were as follows: (a) 76.9% of participants said they were interested or might be interested in doing an exercise program and (b) 81.7% felt they were able or likely able to actually do an exercise program. Participants also indicated that walking was their preferred activity (68.6%) and moderate exercise was their preferred intensity (61.1%). Logistic regression analyses showed that meeting public health guidelines for exercise, being overweight or obese, receiving adjuvant treatment, months since diagnosis, income, marital status, and level of education all influenced exercise preferences. These results suggest that endometrial cancer survivors have unique exercise preferences that are moderated by a number of demographic and medical variables. These findings may have implications for the design and implementation of clinical and population-based exercise interventions for endometrial cancer survivors.
    Regular physical activity may alter estrogen metabolism, a proposed biomarker of breast cancer risk, by shifting metabolism to favor production of 2-hydroxyestrone (2-OHE1). Few studies, however, have examined this question using a... more
    Regular physical activity may alter estrogen metabolism, a proposed biomarker of breast cancer risk, by shifting metabolism to favor production of 2-hydroxyestrone (2-OHE1). Few studies, however, have examined this question using a randomized controlled trial. To examine the effects of 12 weeks of aerobic exercise training on 2-OHE1 and 16alpha-hydroxyestrone (16alpha-OHE1) in premenopausal women. Participants were healthy, regularly menstruating, Caucasian women, 20 to 35 years, body mass index of 18 to 29.9, not using pharmacologic contraceptives, with average or below average fitness [maximal oxygen consumption (VO(2max)), <40 mL/kg/min]. Following a baseline menstrual cycle, participants (N = 32) were randomly assigned to a 12-week aerobic exercise training intervention (n = 17) or usual lifestyle (n = 15). Height, body mass, body composition by dual-energy X-ray absorptiometry, and VO(2max) were measured at baseline and following the intervention. Urine samples were collected in the luteal phase of four consecutive menstrual cycles. The exercise group increased VO(2max) by 14% and had significant, although modest, improvements in fat and lean body mass. No significant between-group differences were observed, however, for the changes in 2-OHE1 (P = 0.944), 16alpha-OHE1 (P = 0.411), or the ratio of 2-OHE1 to 16alpha-OHE1 (P = 0.317). At baseline, there was an inverse association between body fat and 2-OHE1 to 16alpha-OHE1 ratio (r = -0.40; P = 0.044); however, it was the change in lean body mass over the intervention that was positively associated with a change in 2-OHE1 to 16alpha-OHE1 ratio (r = 0.43; P = 0.015). A 12-week aerobic exercise training intervention significantly improved aerobic fitness and body composition but did not alter estrogen metabolism in premenopausal women. Interestingly, an increase in lean body mass was associated with a favorable change in 2-OHE1 to 16alpha-OHE1 ratio.
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