Effect of aerobic exercise on cancer-associated cognitive impairment: A proof-of-concept RCT.

BACKGROUND: Change in cognitive ability is a commonly reported adverse effect by breast cancer survivors. The underlying etiology of cognitive complaints is unclear and to date, there is limited evidence for effective intervention strategies. Exercise has been shown to improve cognitive function in older adults and animal models treated with chemotherapy. This proof-of-concept randomized controlled trial tested the effect of aerobic exercise versus usual lifestyle on cognitive function in postmenopausal breast cancer survivors. METHODS: Women, aged 40 to 65 years, postmenopausal, stages I to IIIA breast cancer, and who self-reported cognitive dysfunction following chemotherapy treatment, were recruited and randomized to a 24-week aerobic exercise intervention (EX; n = 10) or usual lifestyle control (CON; n = 9). Participants completed self-report measures of the impact of cognitive issues on quality of life (Functional Assessment of Cancer Therapy-Cognitive version 3), objective neuropsychological testing, and functional magnetic resonance imaging at baseline and 24 weeks. RESULTS: Compared to CON, EX had a reduced time to complete a processing speed test (trail making test-A) (-14.2 seconds, P < .01; effect size 0.35). Compared to CON, there was no improvement in self-reported cognitive function and effect sizes were small. Interestingly, lack of between-group differences in Stroop behavioral performance was accompanied by functional changes in several brain regions of interest in EX compared to CON at 24 weeks. CONCLUSION: These findings provide preliminary proof-of-concept results for the potential of aerobic exercise to improve cancer-related cognitive impairment and will serve to inform the development of future trials.

Protective effects of acute exercise prior to doxorubicin on cardiac function of breast cancer patients: A proof-of-concept RCT.

BACKGROUND: Preclinical studies have reported that a single treadmill session performed 24h prior to doxorubicin provides cardio-protection. We aimed to characterize the acute change in cardiac function following an initial doxorubicin treatment in humans and determine whether an exercise session performed 24h prior to treatment changes this response. METHODS: Breast cancer patients were randomized to either 30min of vigorous-intensity exercise 24h prior to the first doxorubicin treatment (n=13), or no vigorous exercise for 72h prior to treatment (control, n=11). Echocardiographically-derived left ventricular volumes, longitudinal strain, twist, E/A ratio, and circulating NT-proBNP, a marker of later cardiotoxicity, were measured before and 24-48h after the treatment. RESULTS: Following treatment in the control group, NT-proBNP, end-diastolic and stroke volumes, cardiac output, E/A ratio, strain, diastolic strain rate, twist, and untwist velocity significantly increased (all p≤0.01). Whereas systemic vascular resistance (p<0.01) decreased, and ejection fraction (p=0.02) and systolic strain rate (p<0.01) increased in the exercise group only. Relative to control, the exercise group had a significantly lower NT-proBNP (p<0.01) and a 46% risk reduction of exceeding the cut-point used to exclude acute heart failure. CONCLUSION: The first doxorubicin treatment is associated with acutely increased NT-proBNP, echocardiographic parameters of myocardial relaxation, left ventricular volume overload, and changes in longitudinal strain and twist opposite in direction to documented longer-term changes. An exercise session performed 24h prior to treatment attenuated NT-proBNP release and increased systolic function. Future investigations should verify these findings in a larger cohort and across multiple courses of doxorubicin.

Solid organ transplant recipients: clinical considerations in the application of exercise.

Over 100 000 solid organ transplants are performed worldwide each year and this has a significant impact on physical function and quality of life. However, the capacity for exercise in solid-organ recipients is reduced. Regular physical activity improves most of the indices of fitness in these patients but, with few exceptions, they do not reach the values seen in healthy controls. The reason for the 40-60% reduction in maximal exercise capacity is not clear; the disease process, need for life long immunosuppression and sedentary lifestyle all contribute. The interaction between exercise and immunosuppressing medication merits research as does the specifics of the exercise prescription for these patients. This paper reviews important features of this rapidly expanding group of patients and suggests clinical considerations in the application of exercise in this population.

Subgroup effects in a randomised trial of different types and doses of exercise during breast cancer chemotherapy.

BACKGROUND: The Combined Aerobic and Resistance Exercise Trial tested different types and doses of exercise in breast cancer patients receiving chemotherapy. Here, we explore potential moderators of the exercise training responses. METHODS: Breast cancer patients initiating chemotherapy (N=301) were randomly assigned to three times a week, supervised exercise of a standard dose of 25-30 min of aerobic exercise, a higher dose of 50-60 min of aerobic exercise, or a higher dose of 50-60 min of combined aerobic and resistance exercise. Outcomes were patient-reported symptoms and health-related fitness. Moderators were baseline demographic, exercise/fitness, and cancer variables. RESULTS: Body mass index moderated the effects of the exercise interventions on bodily pain (P for interaction=0.038), endocrine symptoms (P for interaction=0.029), taxane/neuropathy symptoms (P for interaction=0.013), aerobic fitness (P for interaction=0.041), muscular strength (P for interaction=0.007), and fat mass (P for interaction=0.005). In general, healthy weight patients responded better to the higher-dose exercise interventions than overweight/obese patients. Menopausal status, age, and baseline fitness moderated the effects on patient-reported symptoms. Premenopausal, younger, and fitter patients achieved greater benefits from the higher-dose exercise interventions. CONCLUSIONS: Healthy weight, fitter, and premenopausal/younger breast cancer patients receiving chemotherapy are more likely to benefit from higher-dose exercise interventions.

Reproducibility of a laboratory based 20-km time trial evaluation in competitive cyclists using the Velotron Pro ergometer.

The purpose of this study was to evaluate the reliability of a 20-km cycling time trial using the Velotron cycle ergometer in competitive cyclists. Twenty male cyclists (V.O (2max) = 68.5 +/- 3.6 ml . kg (-1) . min (-1); peak power (P (peak)) = 469 +/- 33 W) participated in this study. Each subject performed a V.O (2max) test and 3 separate 20-km time trials (TT1, TT2, and TT3). Data from trials were compared using a one-way ANOVA. Coefficients of variation (CV) and 95 % confidence intervals (CI) were calculated between trials. Values are mean +/- SD unless otherwise noted. Performance time T (tot) (30.03 +/- 1.24, 30.12 +/- 1.21, and 30.14 +/- 1.21 min) and mean absolute power (P (mean)) (326 +/- 35, 323 +/- 35, 322 +/- 34 Watts) were not significantly different across TT1 - TT3. P (mean) was highly related between TT1 - TT2 (r = 0.96; p < 0.01) and TT2 - TT3 (r = 0.97; p < 0.01). A low CV was also demonstrated between trials for P (mean) (TT1 - TT2 = 2.1 %, CI = 1.6 % to 3.1 %; TT2 - TT3 = 1.9 %, CI = 1.4 % to 2.8 %). P (peak) and P (mean) were both correlated to T (tot) in TT1 with P (mean) accounting for most of the variance in T (tot) (R (2) = 0.993). These data show that performance in a 20-km time trial using the Velotron ergometer is highly reproducible in competitive cyclists. Furthermore, the CV variance demonstrated between trials is comparable to that expected during actual performance in elite athletes.

Resting energy expenditure and body mass changes in women during adjuvant chemotherapy for breast cancer.

Weight gain is a commonly reported side effect of adjuvant chemotherapy. A change in resting energy expenditure during treatment has been a suggested mechanism for weight gain. We prospectively measured resting energy expenditure, weight change, and body composition (dual-energy x-ray absorptiometry) in 10 women undergoing adjuvant chemotherapy for breast cancer. There was no change in resting energy expenditure across cycles of chemotherapy (P =.78) or from baseline to the end of treatment (1,189.68 +/- 80.27 vs 1,205.76 +/- 56.71 kcal/d; P =.74). Overall, participants did not gain weight across treatment. However, there was an overall trend toward weight gain (66.3 +/- 5.1 vs 68.2 +/- 5.0 kg; P =.09), and participants did show an increase in total fat mass (24.2 +/- 3.8 vs 26.5 +/- 3.2 kg; P =.04), whereas muscle mass remained the same. Although no change in resting energy expenditure was seen, the observed increase in total fat mass is consistent with a decrease in physical activity level commonly reported with adjuvant chemotherapy treatment of breast cancer, and these body composition changes may have important health implications for survivors.

Intense hypoxic cycle exercise does not alter lung density in competitive male cyclists.

We tested the hypothesis that intense short duration hypoxic exercise would result in an increase in extravascular lung water (EVLW), as evidenced by an increase in lung density. Using computed tomography (CT), baseline lung density was obtained in eight highly trained male cyclists (mean +/- SD: age = 28 +/- 8 years; height = 180 +/- 9 cm; mass = 71.6 +/- 8.2 kg; VO2max= 65.0 +/- 5.2 ml kg min(-1)). Subjects then completed an intense hypoxic exercise challenge on a cycle ergometer and metabolic data, HR and %S(p)O2 were recorded throughout. While breathing 15% O2, subjects performed five 3 km cycling intervals (mean power, 286 +/- 20 W; HR = 91 +/- 4% HRmax) separated by 5 min of recovery. From a resting hypoxic S(p)O2 of 92 +/- 4%, subjects further desaturated during exercise to 76 +/- 3%. CT scans were repeated 76 +/- 10 min (range 63-88 min) following the completion of exercise. There was no change in lung density from pre (0.18 +/- 0.02 g ml(-1)) to post-exercise (0.18 +/- 0.04 g ml(-1)). The substantial reduction in S(p)O2 may be explained by a number of potential mechanisms, including decreased pulmonary diffusion capacity, alveolar hypoventilation, reduced red cell transit time, ventilation/perfusion inequality or a temperature and pH induced rightward-shift in the oxyhaemoglobin dissociation curve. Alternatively, the integrity of the blood gas barrier may have been disrupted without any measurable increase in lung density.

Diffusing capacity and spirometry following a 60-minute dive to 4.5 meters.

The purpose of this study was to assess the contribution of SCUBA to the pulmonary effects of diving to 4.5 meters depth in healthy subjects using a randomized crossover control condition. Ten healthy divers performed two 60-minute 'dives' using SCUBA in a swimming pool. The non-immersed 1 ATA SCUBA control exposure took place at ambient pressure in the laboratory. Thirty minutes prior to, and 30 and 90 minutes post-exposure, FVC (forced vital capacity), FEV1.0 (forced expired volume), peak expiratory flow rate (PEFR), diffusing capacity (DL(co)), heart rate (HR) and temperature were measured. No significant differences were noted in HR, temperature or spirometry between the two conditions. A significant reduction in diffusing capacity occurred at 30 and 90 minutes after the pool dive (9.3% and 15.1%, respectively, p < 0.05). There was no concordant change in DL(co) following the non-immersed 1 ATA SCUBA control. Thus, a pool dive to 4.5 meters for 60 minutes causes a decrease in DL(co), without a change in spirometry, while breathing from SCUBA equipment without immersion causes no significant change in lung function.

Effects of inhaled bronchodilators and corticosteroids on exercise induced arterial hypoxaemia in trained male athletes.

OBJECTIVES: To determine the effect of prophylactic treatment with an inhaled bronchodilator and anti-inflammatory on arterial saturation (SaO2) in trained non-asthmatic male athletes with exercise induced arterial hypoxaemia (EIAH). METHODS: Nine male athletes (mean (SD) age 26.3 (6.7) years, height 182.6 (7.9) cm, weight 79.3 (10.5) kg, VO2MAX 62.3 (6.3) ml/kg/min, SaO2MIN 92.5 (1.1)%) with no history of asthma were tested in two experimental conditions. A combination of a therapeutic dose of salbutamol and fluticasone or an inert placebo was administered in a randomised crossover design for seven days before maximal cycling exercise. Oxygen consumption (VO2), ventilation (VE), heart rate (HR), power output, and SaO2 were monitored during the exercise tests. RESULTS: There were no significant differences between the drug (D) and placebo (P) conditions for minimal SaO2 (D = 93.6 (1.4), P = 93.0 (1.1)%; p = 0.93) VO2MAX (D = 61.5 (7.2), P = 61.9 (6.3) ml/kg/min; p = 0.91), peak power (D = 444.4 (48.3), P = 449.4 (43.9) W; p = 0.90), peak VE (D = 147.8 (19.1), P = 149.2 (15.5) litres/min; p = 0.82), or peak heart rate (D = 182.3 (10.0), P = 180.8 (5.5) beats/min; p = 0.76). CONCLUSIONS: A therapeutic dose of salbutamol and fluticasone did not attenuate EIAH during maximal cycling in a group of trained male non-asthmatic athletes.

The effect of a whole body exercise programme and dragon boat training on arm volume and arm circumference in women treated for breast cancer.

The purpose of this study was to examine the effect of a whole body exercise programme and dragon boat training on changes in arm volume in breast cancer survivors. A total of 16 female breast cancer survivors with no clinical history of lymphoedema volunteered. The 20-week exercise programme consisted of resistance and aerobic exercise with the addition of dragon boat training at week 8. Arm circumference at two sites (CIRC10, CIRC15), arm volume (VOL), and upper body strength (1-RM) were measured at baseline (T1), week 8 (T2), and week 20 (T3). All statistical tests were two-sided (alpha < or = 0.05). No significant differences between the ipsilateral and contralateral upper extremities at any of the three time points were found. All variables significantly increased from T1 to T3 (CIRC10: difference, d = 0.49 cm, 95% confidence interval, CI = 0.25-0.73, P = 0.000; CIRC15: d = 1.33 cm, CI = 0.78-1.88, P = 0.000; VOL: d = 100 mL, CI = 69-130, P = 0.000). As well, 1-RM significantly increased from T1 to T3 (d = 10.8 kg, CI = 5.6-16.1; P = 0.000). In summary, participation in a whole body exercise programme and dragon boat training resulted in a significant increase in upper extremity volume over time. However, the changes were consistent for both arms and the significant gain in upper body muscular strength likely accounted for the increase in arm volume.

The effect of sustained heavy exercise on the development of pulmonary edema in trained male cyclists.

To determine whether intense, prolonged activity can induce transient pulmonary edema, eight highly trained male cyclists (mean +/- S.D.: age, 26.9 +/- 3.0 years; height, 179.9 +/- 5.7 cm; weight, 76.1 +/- 6.5 kg) performed a 45-min endurance cycle test (ECT). V(O2,max) was determined (4.84 +/- 0.4 L min(-1), 63.7 +/- 2.6 ml min(-1) g(-1)) and the intensity of exercise for the ECT was set at 10% below ventilatory threshold (approximately 76% V(O2, max) 300 +/- 25 W). Pre- and post-exercise pulmonary diffusion (DL(CO)) measurements and magnetic resonance imaging of the lung were made. DL(CO) and pulmonary capillary blood volume (VC) decreased 1h post-exercise by 12% (P = 0.004) and 21% (P = 0.017), respectively, but no significant change in membrane diffusing capacity (DM) was found. The magnetic resonance scans demonstrated a 9.4% increase (P = 0.043) in pulmonary extravascular water 90 min post-exercise. These data support the theory that high intensity, sustained exercise in well-trained athletes can result in transient pulmonary edema.

Preventing running injuries. Practical approach for family doctors.

OBJECTIVE: To present a practical approach for preventing running injuries. QUALITY OF EVIDENCE: Much of the research on running injuries is in the form of expert opinion and comparison trials. Recent systematic reviews have summarized research in orthotics, stretching before running, and interventions to prevent soft tissue injuries. MAIN MESSAGE: The most common factors implicated in running injuries are errors in training methods, inappropriate training surfaces and running shoes, malalignment of the leg, and muscle weakness and inflexibility. Runners can reduce risk of injury by using established training programs that gradually increase distance or time of running and provide appropriate rest. Orthoses and heel lifts can correct malalignments of the leg. Running shoes appropriate for runners' foot types should be selected. Lower-extremity strength and flexibility programs should be added to training. Select appropriate surfaces for training and introduce changes gradually. CONCLUSION: Prevention addresses factors proven to cause running injuries. Unfortunately, injury is often the first sign of fault in running programs, so patients should be taught to recognize early symptoms of injury.

Decreased maximal aerobic capacity with use of a triphasic oral contraceptive in highly active women: a randomised controlled trial.

BACKGROUND: Oral contraceptives are commonly used by women athletes. However, their effect on athletic performance is unclear. OBJECTIVES: To examine the effects of a moderate dose, triphasic oral contraceptive on measures of athletic performance in highly trained women athletes. METHODS: This is a double blind, placebo controlled trial in 14 women with ovulatory menstrual cycles and maximal aerobic capacity (VO(2)MAX) >/==" BORDER="0">50 ml/kg/min. Four measures of athletic performance were tested: VO(2)MAX, anaerobic capacity (anaerobic speed test), aerobic endurance (time to fatigue at 90% of VO(2)MAX), and isokinetic strength (Cybex II dynamometer). Height, weight, and six skinfold measurements were also recorded. All these observational tests were completed during both the follicular and mid-luteal phases of an ovulatory menstrual cycle. Cycle phases were confirmed by assaying plasma oestradiol and progesterone. Participants were subsequently randomly assigned to either a tricyclic oral contraceptive or placebo and retested in identical fashion (oral contraceptive phase). RESULTS: Absolute and relative changes in VO(2)MAX from follicular to oral contraceptive phase decreased in the oral contraceptive group by 4.7%, whereas the placebo group showed a slight increase (+1.5%) over the same time period. Two of the women taking oral contraceptive had decreases of 4 and 9 ml/kg/min. In contrast, most women in the placebo group improved or maintained VO(2)MAX. There was also a significant increase in the sum of skinfolds in women taking oral contraceptive compared with those taking placebo (p<0.01). There were no significant changes in other physiological variables (maximum ventilation, heart rate, respiratory exchange ratio, packed cell volume) or measures of performance (anaerobic speed test, aerobic endurance, isokinetic strength) as a function of oral contraceptive treatment. CONCLUSIONS: The decrease in VO(2)MAX that occurs when oral contraceptive is taken may influence elite sporting performance in some women. Further studies are required to determine the mechanisms of this change.

A prospective study of running injuries: the Vancouver Sun Run "In Training" clinics.

OBJECTIVES: Seventeen running training clinics were investigated to determine the number of injuries that occur in a running programme designed to minimise the injury rate for athletes training for a 10 km race. The relative contributions of factors associated with injury were also reported. METHODS: A total of 844 primarily recreational runners were surveyed in three trials on the 4th, 8th, and 12th week of the 13 week programme of the "In Training" running clinics. Participants were classified as injured if they experienced at least a grade 1 injury-that is, pain only after running. Logistic regression modelling and odds ratio calculation were performed for each sex using the following predictor variables: age, body mass index (BMI), previous aerobic activity, running frequency, predominant running surface, arch height, running shoe age, and concurrent cross training. RESULTS: Age played an important part in injury in women: being over 50 years old was a risk factor for overall injury, and being less than 31 years was protective against new injury. Running only one day a week showed a non-significant trend for injury risk in men and was a significant risk factor in women and overall injury. A BMI of > 26 kg/m(2) was reported as protective for men. Running shoe age also significantly contributed to the injury model. Half of the participants who reported an injury had had a previous injury; 42% of these reported that they were not completely rehabilitated on starting the 13 week training programme. An injury rate of 29.5% was recorded across all training clinics surveyed. The knee was the most commonly injured site. CONCLUSIONS: Although age, BMI, running frequency (days a week), and running shoe age were associated with injury, these results do not take into account an adequate measure of exposure time to injury, running experience, or previous injury and should thus be viewed accordingly. In addition, the reason for the discrepancy in injury rate between these 17 clinics requires further study.

Relationship between serum, saliva and urinary cortisol and its implication during recovery from training.

This study examined the relationship among resting cortisol levels measured in serum (SER), saliva (SAL). overnight urine (ON) and 24 h urinary free cortisol (24 h) samples to determine which would be most appropriate for monitoring recovery from the physiological stress imposed by exercise training. Eight (3 female, 5 male) physical education students (X+/-SD age= 22+/-2 y, mass= 73.6+/-17.1 kg; predicted 120m shuttle] VO2max = 3.83+/-1.34 L x min(-1); 51.4+/-8.0 mL x kg(-l) x min(-1)) volunteered. Venous blood, saliva and urine were collected following one day of recovery from training. Morning (0730-0800 h) cortisol was analysed commercially using solid phase radioimmunoassay. Mean resting cortisol concentrations for these samples were in the high end of the normal reference interval previously reported for this population in the literature: SER (656.5+/-122.3 nmol x L(-1)). SAL (41.9+/-12.3 nmol x L(-1)), ON (72.0+/-19.5 nmol x L(-1)) and 24 h (170.8 +/-58.7 nmol x day(-1)). Intraclass correlation coefficients (R) showed a high correlation between 24 h versus SER (R=0.99), SAL (R=0.97), and ON (R=0.97) cortisol, and between SER and SAL cortisol (r=0.99) Limits of agreement analysis to determine measurement error also revealed significant correlations (r2=0.60-0.99) between the dependent variables. In conclusion, the strong intraclass correlation coefficient between 24 h cortisol versus SAL and SER suggests that either sample can be used to monitor cortisol hormone during a recovery period from exercise training. The use of SAL samples for cortisol analysis may have many advantages due to its non-invasive nature.

Acute hypervolemia lengthens red cell pulmonary transit time during exercise in endurance athletes.

The purpose was to determine if acute plasma volume expansion (PVE) changed red-cell pulmonary transit time (PTT) during severe exercise. Twelve endurance athletes performed 6.5 min of severe cycling exercise on different days. Pentaspan [(500 ml, infusion condition, I] or placebo [(60 ml saline), non-infusion condition, N] were infused prior to exercise. Blood gas tensions, PTT, multigated acquisition (MUGA) derived cardiac output, and oxygen uptake were measured during exercise. PTT was measured during minute 3 of exercise by radionuclide cardiography. Arterial P(O(2)) (Pa(O(2))), and alveolar-arterial oxygen pressure difference (AaD(O(2))) at minute 3 of exercise did not differ between conditions. Mean PTT at minute 3 of exercise was 0.3 sec longer in the I condition (P=0.002). However, the change in PTT between conditions was not correlated to the change in either Pa(O(2)) or AaD(O(2)). We conclude that PVE slows (lengthens) PTT without affecting pulmonary gas exchange. Therefore, rapid PTT may not be related to hypoxemia during exercise.

The lactate paradox in human high-altitude physiological performance.

For many years, physiologists have puzzled over the observation that, during maximum aerobic exercise, high-altitude natives generate lower-than-expected amounts of lactate; the higher the altitude, the lower the postexercise blood lactate peak. This paradoxical situation may be caused mainly by upregulated metabolic control contributions from cell ATP demand and ATP supply pathways.

A retrospective case-control analysis of 2002 running injuries.

OBJECTIVE: To provide an extensive and up to date database for specific running related injuries, across the sexes, as seen at a primary care sports medicine facility, and to assess the relative risk for individual injuries based on investigation of selected risk factors. METHODS: Patient data were recorded by doctors at the Allan McGavin Sports Medicine Centre over a two year period. They included assessment of anthropometric, training, and biomechanical information. A model was constructed (with odds ratios and their 95% confidence intervals) of possible contributing factors using a dependent variable of runners with a specific injury and comparing them with a control group of runners who experienced a different injury. Variables included in the model were: height, weight, body mass index, age, activity history, weekly activity, history of injury, and calibre of runner. RESULTS: Most of the study group were women (54%). Some injuries occurred with a significantly higher frequency in one sex. Being less than 34 years old was reported as a risk factor across the sexes for patellofemoral pain syndrome, and in men for iliotibial band friction syndrome, patellar tendinopathy, and tibial stress syndrome. Being active for less than 8.5 years was positively associated with injury in both sexes for tibial stress syndrome; and women with a body mass index less than 21 kg/m(2) were at a significantly higher risk for tibial stress fractures and spinal injuries. Patellofemoral pain syndrome was the most common injury, followed by iliotibial band friction syndrome, plantar fasciitis, meniscal injuries of the knee, and tibial stress syndrome. CONCLUSIONS: Although various risk factors were shown to be positively associated with a risk for, or protection from, specific injuries, future research should include a non-injured control group and a more precise measure of weekly running distance and running experience to validate these results.

Measurement of upper extremity volume in women after axillary dissection for breast cancer.

OBJECTIVE: To determine if 2 methods of calculating upper extremity volume (using arm circumferences) can substitute for water displacement volumetry. DESIGN: Interrater and test-retest reliability and limits of agreement for volume measures. SETTING: University. PARTICIPANTS: Twenty-five women at risk for lymphedema who had undergone axillary lymph node dissection surgery for breast cancer. INTERVENTIONS: Circumference and volume measurements of both upper extremities were taken by 2 physical therapists at an initial visit and by 1 of the therapists 1 week later. MAIN OUTCOME MEASURES: Intraclass correlation coefficients (ICCs) were calculated to analyze measurement reliability. Pearson's product-moment correlation coefficient (r) was used to evaluate the relationship between volumetry and calculated truncated cone volumes. Limits of agreement were calculated to determine the level of agreement between the 2 measurement methods. RESULTS: Interrater and test-retest reliability ICCs for circumferential and volumetric data were .99 and .99, respectively. Pearson's r values were .93 and .97 for the single truncated cone and the summed truncated cone volume calculations, respectively. Limits of agreement (mean +/- 2 standard deviations) were -52 +/- 334mL and -40 +/- 234mL, respectively, between volumetry and the single truncated cone and summed truncated cone calculations. CONCLUSIONS: Calculated and volumetric measurements in this population are both reliable and closely related, but do not agree with each another, and thus should not be used interchangeably.

Markers of inflammation and myofibrillar proteins following eccentric exercise in humans.

The purpose of this study was to examine the time-course and relationships of technetium-99m (99mTc) neutrophils in muscle, interleukin-6 (IL-6), myosin heavy chain fragments (MHC), eccentric torque, and delayed onset muscle soreness (DOMS) following eccentric exercise in humans. Twelve male subjects completed a pre-test DOMS questionnaire, performed a strength test and had 100 ml blood withdrawn for analysis of plasma IL-6 and MHC content. The neutrophils were separated, labelled with 99mTc, and re-infused into the subjects immediately before the exercise. Following 300 eccentric repetitions of the right quadriceps muscles on an isokinetic dynamometer, the subjects had 10 ml of blood withdrawn with repeated the eccentric torque exercise tests and DOMS questionnaire at 0, 2, 4, 6, 20, 24, 48, 72 h, and 6 and 9 days. Bilateral images of the quadriceps muscles were taken at 2, 4, and 6 h. Computer analysis of regions of interest was used to determine the average count per pixel. The 99mTc neutrophils and IL-6 increased up to 6 h post-exercise (P < 0.05). The neutrophils were greater in the exercised muscle than the non-exercised muscle (P < 0.01). The DOMS was increased from 0 to 48 h, eccentric torque decreased from 2 to 24 h, and MHC peaked at 72 h post-exercise (P < 0.001). Significant relationships were found between IL-6 and 2 h and DOMS at 24 h post-exercise (r = 0.68) and assessment of the magnitude of change between IL-6 and MHC (r = 0.66). These findings suggest a relationship between damage to the contractile proteins and inflammation, and that DOMS is associated with inflammation but not with muscle damage.