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Approaches to Teaching in Kinesiology
This is a syllabus for a new class in the semester system for the Kinesiology department. The syllabus is for KINE 4700, Clinical Exercise Physiology. This course upper division course will review common clinical diseases, disorders, and conditions. Students will review the epidemiology, physiology, and pathophysiology of these conditions. Students will participate in active learning activities, such as the development of videos, in which students will demonstrate and explain how different exercise movements will be utilized. The course will follow an outline derived from information gained in the textbook from the world’s premier sports medicine organization, The American College of Sports Medicine. Grading for the course will be based on a combination of traditional examinations and quizzes, along with the laboratory activities and related active learning projects
Cardiorespiratory Fitness and Cardiovascular Disease Risk Factors in Postmenopausal Women
In spite of the reductions in cardiovascular disease mortality over the last several years, cardiovascular disease remains the number one cause of death in the U.S. Prior to menopause, women have approximately 2.5-4.5 times lower risk of cardiovascular disease than do men of a similar age. Within about 10 years following menopause, however, the rate in women becomes similar to that seen in men. Increased cardiorespiratory fitness and use of hormone replacement have been suggested as ways to improve the cardiovascular disease (CVD) risk profile. Unfortunately, very little is known about the effect of cardiorespiratory fitness on the CVD risk profile in postmenopausal women, and if there is an effect whether this effect is independent of hormone status. Therefore, the purpose of this study was to determine if cardiorespiratory fitness is associated with an improvement in the CVD risks of total cholesterol, HDL cholesterol, TC/HDL ratio, triglycerides, and fibrinogen, in postmenopausal women. Records of non smoking postmenopausal women who completed a preventive medicine physical examination, in the Aerobic Center Longitudinal Study between 1987 and 1995, were examined. Cardiorespiratory fitness was determined by total treadmill time to exhaustion on a graded exercise test, CVD risk factors were assessed via blood analysis. On cross sectional analysis, fitness was statistically significantly associated with a decrease in total cholesterol (R2 =.08), the total cholesterol/HDL cholesterol ratio (R2 = .12), triglycerides (R2 = .09), and fibrinogen (R2 = .06), and an increase in HDL cholesterol (R2 = .04). All relationships were significant at a p value of \u3c0.005. After statistically controlling for hormone status, age, year of testing, and blood glucose, each CVD risk factor remained significantly associated with cardiorespiratory fitness (p\u3c0.05). This study indicates that cardiorespiratory fitness is an important independent determinant of blood lipid and fibrinogen levels in nonsmoking postmenopausal women
Active Video/Arcade Games (Exergaming) and Energy Expenditure in College Students.
Video games have become increasingly popular among young adults. The purpose of this pilot study was to determine if interactive video/arcade games, requiring physical activity to play, increase the energy expenditure (EE) and heart rate (HR) of young adults enough to elicit a training response. Thirteen male and female participants 26.6 ± 5.7 years of age were in the study. Participants were familiarized with equipment and allowed to practice with three games: (1) moving and striking lighted pads, (2) riding a bike to increase the pace of a race car, and (3) boxing against a video simulated opponent. A portable metabolic cart and HR monitor were attached to participants to measure baseline and exercise values. Participants could play any of the three games for 30 minutes while metabolic and HR data were collected. Exercise data were compared to baseline measures, and the 3 games were compared for EE. Paired sample t-tests showed baseline and exercise values differed for HR (t(12) = -18.91, p \u3c 0.01), and EE (t(12) = -15.62, p \u3c 0.01). The boxing game provided the highest VO2 (17.47 ± 4.79 ml·kg·-1min-1). Participants achieved 60% or better of their HR reserve (162.82 ± 10.78 beats·min-1), well within the ACSM guidelines for a training HR. Caloric expenditure during the 30-minute exercise session (226. 07 ± 48.68) is also within the ACSM recommendations for daily physical activity. Thus, interactive video/arcade games that require physical activity to play can be utilized as part of an overall aerobic exercise program
Racial/Ethnic Differences in Bone Mineral Density of Young Adults
An estimated 1.5 million people suffer a bone disease-related fracture every year. Most work investigating bone mineral density (BMD) focuses on post-menopausal females but a report from the Surgeon General in 2004 stated that of particular concern are men, racial and ethnic minorities, poor individuals, individuals with disabilities, and individuals living in rural areas. The purpose of this study was to examine the racial/ethnic differences in bone mineral density of young adults and to investigate any correlations with variables suggested to influence BMD. BMD was assessed at a younger age than most studies based on the assumption that osteoporosis is a pediatric disorder that manifests in old age. Whole-body BMD, percent body fat (BF), fat mass (FM), and lean mass (LM) of 103 college-aged Blacks, Whites, and Hispanics (18 – 34 years of age) were measured using a Lunar Prodigy Dual Energy X-ray Absorptiometry (DEXA). Blacks and Whites were taller than Hispanics. Blacks had higher BMD than Whites and Hispanics. Blacks and Whites had higher t-scores than Hispanics. Weight and LM correlated with BMD for all three groups. Height correlated with BMD for Blacks only. FM correlated with BMD for Hispanics only. In conclusion, BMD is suggested to be higher in Blacks than Whites and Hispanics. LM is suggested to be an important component of bone health. It is important to stress resistance training for building and maintaining bone health throughout life
Assessment of muscle function using hybrid PET/MRI:comparison of <sup>18</sup>F-FDG PET and T2-weighted MRI for quantifying muscle activation in human subjects
PURPOSE: The aim of this study was to determine the relationship between relative glucose uptake and MRI T (2) changes in skeletal muscles following resistance exercise using simultaneous PET/MRI scans. METHODS: Ten young healthy recreationally active men (age 21 – 28 years) were injected with (18)F-FDG while activating the quadriceps of one leg with repeated knee extension exercises followed by hand-grip exercises for one arm. Immediately following the exercises, the subjects were scanned simultaneously with (18)F-FDG PET/MRI and muscle groups were evaluated for increases in (18)F-FDG uptake and MRI T (2) values. RESULTS: A significant linear correlation between (18)F-FDG uptake and changes in muscle T (2) (R (2) = 0.71) was found. for both small and large muscles and in voxel to voxel comparisons. Despite large intersubject differences in muscle recruitment, the linear correlation between (18)F-FDG uptake and changes in muscle T (2) did not vary among subjects. CONCLUSION: This is the first assessment of skeletal muscle activation using hybrid PET/MRI and the first study to demonstrate a high correlation between (18)F-FDG uptake and changes in muscle T (2) with physical exercise. Accordingly, it seems that changes in muscle T (2) may be used as a surrogate marker for glucose uptake and lead to an improved insight into the metabolic changes that occur with muscle activation. Such knowledge may lead to improved treatment strategies in patients with neuromuscular pathologies such as stroke, spinal cord injuries and muscular dystrophies
A Nordic survey of CT doses in hybrid PET/CT and SPECT/CT examinations
Background Computed tomography (CT) scans are routinely performed in positron emission tomography (PET) and single photon emission computed tomography (SPECT) examinations globally, yet few surveys have been conducted to gather national diagnostic reference level (NDRL) data for CT radiation doses in positron emission tomography/computed tomography (PET/CT) and single photon emission computed tomography/computed tomography (SPECT/CT). In this first Nordic-wide study of CT doses in hybrid imaging, Nordic NDRL CT doses are suggested for PET/CT and SPECT/CT examinations specific to the clinical purpose of CT, and the scope for optimisation is evaluated. Data on hybrid imaging CT exposures and clinical purpose of CT were gathered for 5 PET/CT and 8 SPECT/CT examinations via designed booklet. For each included dataset for a given facility and scanner type, the computed tomography dose index by volume (CTDIvol) and dose length product (DLP) was interpolated for a 75-kg person (referred to as CTDIvol,75kg and DLP75kg). Suggested NDRL (75th percentile) and achievable doses (50th percentile) were determined for CTDIvol,75kg and DLP75kg according to clinical purpose of CT. Differences in maximum and minimum doses (derived for a 75-kg patient) between facilities were also calculated for each examination and clinical purpose. Results Data were processed from 83 scanners from 43 facilities. Data were sufficient to suggest Nordic NDRL CT doses for the following: PET/CT oncology (localisation/characterisation, 15 systems); infection/inflammation (localisation/characterisation, 13 systems); brain (attenuation correction (AC) only, 11 systems); cardiac PET/CT and SPECT/CT (AC only, 30 systems); SPECT/CT lung (localisation/characterisation, 12 systems); bone (localisation/characterisation, 30 systems); and parathyroid (localisation/characterisation, 13 systems). Great variations in dose were seen for all aforementioned examinations. Greatest differences in DLP75kg for each examination, specific to clinical purpose, were as follows: SPECT/CT lung AC only (27.4); PET/CT and SPECT/CT cardiac AC only (19.6); infection/inflammation AC only (18.1); PET/CT brain localisation/characterisation (16.8); SPECT/CT bone localisation/characterisation (10.0); PET/CT oncology AC only (9.0); and SPECT/CT parathyroid localisation/characterisation (7.8). Conclusions Suggested Nordic NDRL CT doses are presented according to clinical purpose of CT for PET/CT oncology, infection/inflammation, brain, PET/CT and SPECT/CT cardiac, and SPECT/CT lung, bone, and parathyroid. The large variation in doses suggests great scope for optimisation in all 8 examinations.Peer reviewe
Effects of dynamic [18F]NaF PET scan duration on kinetic uptake parameters in the knee
IntroductionAccurately estimating bone perfusion and metabolism using [18F]NaF kinetics from shorter scan times could help address concerns related to patient comfort, motion, and throughput for PET scans. We examined the impact of changing the PET scan duration on the accuracy of [18F]NaF kinetic parameters in the knee.MethodsBoth knees of twenty participants with and without osteoarthritis were scanned using a hybrid PET-MRI system (53 ± 13 years, BMI 25.9 ± 4.2 kg/m2, 13 female). Seventeen participants were scanned for 54 ± 2 min, and an additional three participants were scanned for 75 min. Patlak Ki and Hawkins kinetic parameters (Ki, K1, extraction fraction) were assessed using 50- or 75-minutes of scan data as well as for scan durations that were retrospectively shortened. The error of the kinetic uptake parameters was calculated in bone regions throughout the knee.ResultsThe mean error of Patlak Ki, Hawkins Ki, K1, and extraction fraction was less than 10% for scan durations exceeding 30 min and decreased with increasing scan duration.ConclusionsThe length of dynamic data acquisition can be reduced to as short as 30 min while retaining accuracy within the limits of reproducibility of Hawkins kinetic uptake parameters
Changes in systemic GDF15 across the adult lifespan and their impact on maximal muscle power: the Copenhagen Sarcopenia Study
Background Although growth differentiation factor 15 (GDF15) is known to increase with disease and is associated
with low physical performance, the role of GDF15 in normal ageing is still not fully understood. Specifically, the influ ence of circulating GDF15 on impairments in maximal muscle power (a major contributor to functional limitations) and
the underlying components has not been investigated.
Methods Data from 1305 healthy women and men aged 20 to 93 years from The Copenhagen Sarcopenia Study were
analysed. Circulating levels of GDF15 and markers of inflammation (tumor necrosis factor-alpha, interleukin-6, and
high-sensitivity C-reactive protein) were measured by ELISA (R&D Systems) and multiplex bead-based immunoassays
(Bio-Rad). Relative (normalized to body mass), allometric (normalized to height squared), and specific (normalized to
leg muscle mass) muscle power were assessed by the Nottingham power rig [leg extension power (LEP)] and the 30 s
sit-to-stand (STS) muscle power test. Total body fat, visceral fat, and leg lean mass were assessed by dual energy X-ray
absorptiometry. Leg skeletal muscle index was measured as leg lean mass normalized to body height squared.
Results Systemic levels of GDF15 increased progressively as a function of age in women (1.1 ± 0.4 pg·mL 1
·year 1
)
and men (3.3 ± 0.6 pg·mL 1
·year 1
) (both P < 0.05). Notably, GDF15 increased at a faster rate from the age of 65 years
in women (11.5 ± 1.2 pg·mL 1
·year 1
, P < 0.05) and 70 years in men (19.3 ± 2.3 pg·mL 1
·year 1
, P < 0.05), resulting
in higher GDF15 levels in men compared with women above the age of 65 years (P < 0.05). Independently of age and
circulatory markers of inflammation, GDF15 was negatively correlated to relative STS power (P < 0.05) but not LEP, in
both women and men. These findings were mainly explained by negative associations of GDF15 with specific STS
power in women and men (both P < 0.05).
Conclusions A J-shaped relationship between age and systemic GDF15 was observed, with men at older age showing
steeper increases and elevated GDF15 levels compared with women. Importantly, circulating GDF15 was indepen dently and negatively associated with relative STS power, supporting the potential role of GDF15 as a sensitive
biomarker of frailty in older people
Kidney oxygenation, perfusion and blood flow in people with and without type 1 diabetes
Background We used magnetic resonance imaging (MRI) to study kidney energetics in persons with and without type 1 diabetes (T1D). Methods In a cross-sectional study, 15 persons with T1D and albuminuria and 15 non-diabetic controls (CONs) underwent multiparametric MRI (3 Tesla Philips Scanner) to quantify renal cortical and medullary oxygenation (R-2*, higher values correspond to higher deoxyhaemoglobin concentration), renal perfusion (arterial spin labelling) and renal artery blood flow (phase contrast). Analyses were adjusted for age, sex, systolic blood pressure, plasma haemoglobin, body mass index and estimated glomerular filtration rate (eGFR). Results Participants with T1D had a higher median (Q1; Q3) urine albumin creatinine ratio (UACR) than CONs [46 (21; 58) versus 4 (3; 6) mg/g; P < .0001] and a lower mean +/- SD eGFR (73 +/- 32 mL/min/1.73 m(2) versus 88 +/- 15 mL/min/1.73 m(2); P = .12), although not significantly. Mean medullary R-2* was lower in T1D (34 +/- 6/s versus 38 +/- 5/s; P < .01) corresponding to a higher oxygenation. R-2* was not different in the cortex. Cortical perfusion was lower in T1D (163 +/- 40 versus 224 +/- 49 mL/100 g/min; P < .001). Renal artery blood flow was lower in T1D than in CONs (360 +/- 130 versus 430 +/- 113 mL/min; P = .05). In T1D, lower cortical oxygenation and renal artery blood flow were both associated with higher UACR and lower eGFR (P < .05). Conclusions Participants with T1D and albuminuria exhibited higher medullary oxygenation than CONs, despite lower cortical perfusion and renal artery blood flow. This might reflect perturbed kidney energetics leading to a higher setpoint of medullary oxygenation in T1D. Lower cortical oxygenation and renal artery blood flow were associated with higher UACR and lower eGFR in T1D.Peer reviewe
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