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In many kinesiology and health care science departments in the United States, there is a mismatch between the demographic composition of the student population and the faculty cohort. That is, although student populations are more diverse, the faculty cohort does not reflect this same diversity. The purpose of this paper is threefold: (a) Provide background information on the faculty–student mismatch, (b) discuss reactive strategies to increase diversity among a faculty cohort, and (c) discuss proactive strategies to increase diversity among a faculty cohort. Our approach is pragmatic and concise, which will give the reader various strategies they can incorporate to increase diversity in their faculty cohort. [ABSTRACT FROM AUTHOR]

Mitochondria, through oxidative phosphorylation, are crucial for energy production. Disease, genetic impairment, or deconditioning can harm muscle mitochondria, affecting energy production. Endurance training enhances mitochondrial function but assumes mobility. Individuals with limited mobility lack effective treatments for mitochondrial dysfunction because of disease or aging. Mitochondrial transplantation replaces native mitochondria that have been damaged with viable, respiration-competent mitochondria. Here, we used a rodent model selectively bred for low-capacity running (LCR), which exhibits innate mitochondrial dysfunction in the hind limb muscles. Hence, the purpose of this study was to use a distinct breed of rats (i.e., LCR) that display hereditary skeletal muscle mitochondrial dysfunction to evaluate the consequences of mitochondrial transplantation. We hypothesized that the transplantation of mitochondria would effectively alleviate mitochondrial dysfunction in the hind limb muscles of rats when compared with placebo injections. In addition, we hypothesized that rats receiving the mitochondrial transplantation would experience an improvement in their functional capacity, as evaluated through incremental treadmill testing. Twelve aged LCR male rats (18 months old) were randomized into 2 groups (placebo or mitochondrial trans- plantation). One LCR rat of the same age and sex was used as the donor to isolate mitochondria from the hindlimb muscles. Isolated mitochondria were injected into both hindlimb muscles (quadriceps femoris, tibialis anterior (TA), and gastrocnemius complex) of a subset LCR (n = 6; LCR-M) rats. The remaining LCR (n = 5; LCR-P) subset received a placebo injection containing only the vehicle without the isolated mitochondria. Four weeks after mitochondrial transplantation, rodents were euthanized and hindlimb muscles harvested. The results indicated a significant (p < 0.05) increase in mitochondrial markers for glycolytic (plantaris and TA) and mixed (quadricep femoris) muscles, but not oxidative muscle (soleus). Moreover, we found significant (p < 0.05) epigenetic changes (i.e., hypomethylation) at the global and site-specific levels for a key mitochondrial regulator (transcription factor A mitochondrial) between the placebo and mitochondrial transplantation groups. To our knowledge, this is the first study to examine the efficacy of mitochondrial transplantation in a rodent model of aging with congenital skeletal muscle dysfunction. [ABSTRACT FROM AUTHOR]

The placebo effect occurs when a desired outcome is experienced due to the belief that a treatment is effective, even in the absence of an active ingredient. One explanation for this effect is based on a person's expectations of a drug or supplement. Although caffeine's effects on sports performance have been studied, little is known about how expectations of caffeine affect neuromuscular fatigue during continuous muscle action. The physical working capacity at the fatigue threshold (PWCFT) can be used to assess neuromuscular fatigue noninvasively using surface electromyography. Thus, the purpose of this study was to investigate whether caffeine expectancy influences PWCFT. We hypothesized that regardless of expectancy, caffeine consumption would delay neuromuscular fatigue. The study involved 8 healthy college-aged men (mean ± SEM: age, 25.6 ± 1.0 years) who visited the laboratory on 4 occasions, each separated by 7 days. The subjects completed 4 experimental conditions, in random order, where they were told that they were consuming caffeine or placebo and either received caffeine or placebo. After consuming the drink, the subjects remained in the laboratory for an hour and then performed an incremental exercise test. The results showed that the condition where subjects were told that they were consuming caffeine and received caffeine had significantly higher mean values for maximal power output (F(3, 21) = 11.75; p < 0.001), PWCFT (F(3, 21) = 12.28; p < 0.001), PWCFT (%maximal power output; F(3, 21) = 8.75; p < 0.001), and heart rate at end exercise (%predicted; F(3, 21) = 3.83; p = 0.025) compared with the 2 conditions where placebo was received. However, no statistically significant mean differences were found from the condition where subjects were told that they were consuming placebo but consuming caffeine. This suggests that a person's expectancy and potential somatic response may serve as a cue for how an ergogenic aid or placebo could affect subsequent performance. [ABSTRACT FROM AUTHOR]

BackgroundThere is still limited information on systemic inflammation in alpha-1-antitrypsin-deficient (AATD) COPD patients and what effect alpha-1-antitrypsin augmentation therapy and/or exercise might have on circulating inflammatory cytokines. We hypothesized that AATD COPD patients on augmentation therapy (AATD + AUG) would have lower circulating and skeletal muscle inflammatory cytokines compared to AATD COPD patients not receiving augmentation therapy (AATD-AUG) and/or the typical non-AATD (COPD) patient. We also hypothesized that cytokine response to exercise would be lower in AATD + AUG compared to AATD-AUG or COPD subjects.MethodsArterial and femoral venous concentration and skeletal muscle expression of TNFα, IL-6, IL-1β and CRP were measured at rest, during and up to 4-hours after 50% maximal 1-hour knee extensor exercise in all COPD patient groups, including 2 additional groups (i.e. AATD with normal lung function, and healthy age-/activity-matched controls).ResultsCirculating CRP was higher in AATD + AUG (4.7 ± 1.6 mg/dL) and AATD-AUG (3.3 ± 1.2 mg/dL) compared to healthy controls (1.5 ± 0.3 mg/dL, p < 0.05), but lower in AATD compared to non-AATD-COPD patients (6.1 ± 2.6 mg/dL, p < 0.05). TNFα, IL-6 and IL-1β were significantly increased by 1.7-, 1.7-, and 4.7-fold, respectively, in non-AATD COPD compared to AATD COPD (p < 0.05), and 1.3-, 1.7-, and 2.2-fold, respectively, compared to healthy subjects (p < 0.05). Skeletal muscle TNFα was on average 3-4 fold greater in AATD-AUG compared to the other groups (p < 0.05). Exercise showed no effect on these cytokines in any of our patient groups.ConclusionThese data show that AATD COPD patients do not experience the same chronic systemic inflammation and exhibit reduced inflammation compared to non-AATD COPD patients. Augmentation therapy may help to improve muscle efflux of TNFα and reduce muscle TNFα concentration, but showed no effect on IL-6, IL-1β or CRP.

Background: Mitochondria are the 'powerhouses of cells' and progressive mitochondrial dysfunction is a hallmark of aging in skeletal muscle. Although different forms of exercise modality appear to be beneficial to attenuate aging-induced mitochondrial dysfunction, it presupposes that the individual has a requisite level of mobility. Moreover, non-exercise alternatives (i.e., nutraceuticals or pharmacological agents) to improve skeletal muscle bioenergetics require time to be effective in the target tissue and have another limitation in that they act systemically and not locally where needed. Mitochondrial transplantation represents a novel directed therapy designed to enhance energy production of tissues impacted by defective mitochondria. To date, no studies have used mitochondrial transplantation as an intervention to attenuate aging-induced skeletal muscle mitochondrial dysfunction. The purpose of this investigation, therefore, was to determine whether mitochondrial transplantation can enhance skeletal muscle bioenergetics in an aging rodent model. We hypothesized that mitochondrial transplantation would result in sustained skeletal muscle bioenergetics leading to improved functional capacity. Methods: Fifteen female mice (24 months old) were randomized into two groups (placebo or mitochondrial transplantation). Isolated mitochondria from a donor mouse of the same sex and age were transplanted into the hindlimb muscles of recipient mice (quadriceps femoris, tibialis anterior, and gastrocnemius complex). Results: The results indicated significant increases (ranging between ~36% and ~65%) in basal cytochrome c oxidase and citrate synthase activity as well as ATP levels in mice receiving mitochondrial transplantation relative to the placebo. Moreover, there were significant increases (approx. two-fold) in protein expression of mitochondrial markers in both glycolytic and oxidative muscles. These enhancements in the muscle translated to significant improvements in exercise tolerance. Conclusions: This study provides initial evidence showing how mitochondrial transplantation can promote skeletal muscle bioenergetics in an aging rodent model. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to determine whether cold therapy after the first exercise test influences the physical working capacity at the fatigue threshold (PWCFT) during the second exercise test. We hypothesized that cold therapy would delay the onset of PWCFT for the second exercise test relative to the control visit (i.e., no cold therapy). Methods: Eight healthy college-aged men volunteered for the present study. For each of the two visits, subjects performed incremental, single-leg, knee-extensor ergometer, followed by either resting for 30 min (control visit) or having a cold pack applied for 15 min and then resting for 15 min (experimental visit). Then, the same exercise test was performed. The order of visits (control vs. experimental) was randomized for each subject. The exercise indices and PWCFT were determined for each of the two visits and statistically analyzed using two-way repeated measures analysis of variance. Results: The results indicate no significant (p > 0.05) mean differences for maximal power output, heart rate at end-exercise, and PWCFT between the control and cold therapy visits. Moreover, there were no significant (p > 0.05) mean differences between the first and second exercise workbout within each visit. Conclusions: The findings of this study suggest that cold therapy did not influence neuromuscular fatigue. [ABSTRACT FROM AUTHOR]

Examined the relationship between commonly used indicators of knowledge and actual knowledge in five areas among fitness trainers. Data from the Fitness Instructors Knowledge Assessment indicated that a bachelor's degree in the field of exercise science and possession of one of two specific certifications strongly predicted a trainer's knowledge, whereas years of experience did not relate to knowledge. (SM)

The purpose of this study was to validate the Physical Working Capacity at the Heart Rate Threshold ([PWC.sub.HRT]) and Physical Working Capacity at the Oxygen Consumption Threshold (PWC [Vo.sub.2]) tests by 1) using individual power vs. duration relationships to estimate the times to exhaustion (ETTE) at the [PWC.sub.HRT] and PWC [Vo.sub.2], and 2) comparing the power outputs and ETTE values of the [PWC.sub.HRT] and PWC [Vo.sub.2] with those of the ventilatory threshold (VT). Ten adults (mean age [+ or -] SD = 23 [+ or -] 1 years) performed an incremental test to exhaustion on a cycle ergometer for the determination of [Vo.sub.2]peak and VT. The subjects also performed four randomly ordered workbouts to exhaustion at different power outputs (ranging from 98 to 246 W) to determine the PWC [Vo.sub.2], [PWC.sub.HRT], and power vs. duration relationship. Power curve analyses (y = [ax.sup.b]) were used to define the hyperbolic power vs. duration relationship for each subject and to determine the ETTE at the PWC [Vo.sub.2], [PWC.sub.HRT], and VT. Two separate one-way repeated-measures analyses of variance indicated that there were significant differences among the fatigue thresholds (PWC [Vo.sub.2] > [PWC.sub.HRT]) and ETTE values ([PWC.sub.HRT] > PWC [Vo.sub.2]): PWC [Vo.sub.2] (mean [+ or -] SD = 147 [+ or -] 43 W; ETTE = 21 [+ or -] 3 minutes), [PWC.sub.HRT] (136 [+ or -] 37 W; ETTE = 29 [+ or -] 6 minutes), and VT (143 [+ or -] 44 W; ETTE = 27 [+ or -] 11 minutes). These findings were consistent with previous studies that indicated that the [PWC.sub.HRT] occurred at a lower power output than the PWC [Vo.sub.2]. Furthermore, the [PWC.sub.HRT] was maintained for a mean of 29 minutes, whereas the PWC [Vo.sub.2] and VT were maintained for 21 and 27 minutes, respectively. These findings indicate that the ETTE values for the PWC [Vo.sub.2] and [PWC.sub.HRT] were substantially less than those suggested in previous studies. KEY WORDS fatigue threshold, PWC [Vo.sub.2], [PWC.sub.HRT], VT

The purposes of this study were to 1) compare the patterns of responses for plasma ammonia concentration ([N[H.sub.3]]) during moderate- vs. heavy-intensity cycle ergometry, and 2) examine the relationship between the [Vo.sub.2] slow component ([Vo.sub.2SC]) and plasma [N[H.sub.3]]. Thirteen healthy, untrained men (mean [+ or -] SEM age = 24.8 [+ or -] 0.6 years) performed a total of eight constant power output exercises (7 minutes in duration) at two different intensities (moderate, 60% gas exchange threshold [GET] = 60% of the gas exchange threshold; and heavy, [DELTA]50% = 50% of the difference between GET and [Vo.sub.2]max). Blood was collected from an antecubital vein before the exercise, during the last 3 minutes of the 6-minute warm-up, and during each minute of the 7-minute constant power output workbout. The time course of changes in plasma [N[H.sub.3]] and [Vo.sub.2] during the two constant power output exercise intensities were assessed separately using 2 (intensity) x 7 (time) repeated-measures analyses of variance. For 60% GET, there were no significant differences in the mean normalized plasma [N[H.sub.3]] during the 7-minute workbout. For [DELTA]50%, there was a significant increase in the mean normalized plasma [N[H.sub.3]] during the 7-minute workbout. These findings suggest a potential relationship between exercise-induced hyperammonemia and the [Vo.sub.2SC] during heavy-intensity exercise. KEY WORDS ammonia concentration, AMP deaminase, bioenergetics, muscle energetics, oxygen uptake kinetics

The purpose of the present study was to examine the acute effects of a caffeine-containing supplement (SUPP) on one-repetition maximum (1-RM) bench press strength and time to running exhaustion (TRE) at a velocity that corresponded to 85% of the peak oxygen uptake (V[O.sub.2]peak). The study used a double-blinded, placebo-controlled, crossover design. Thirty-one men (mean [+ or -] SD age = 23.0 [+ or -] 2.6 years) were randomly assigned to take either the SUPP or placebo (PLAC) first. The SUPP contained 201 mg of caffeine, and the PLAC was microcrystalline cellulose. All subjects were tested for 1-RM bench press strength and TRE at 45 minutes after taking either the SUPP or PLAC. After 1 week of rest, the subjects returned to the laboratory and ingested the opposite substance (SUPP or PLAC) from what was taken during the previous visit. The 1-RM bench press and TRE tests were then performed in the same manner as before. The results indicated that the SUPP had no effect on 1-RM bench press strength or TRE at 85% V[O.sub.2]peak. It is possible that the acute effects of caffeine are affected by differences in training status and/or the relative intensity of the exercise task. Future studies should examine these issues, in addition to testing the acute effects of various caffeine doses on performance during maximal strength, power, and aerobic activities. These findings do not, however, support the use of caffeine as an ergogenic aid in untrained to moderately trained individuals.

The purpose of the present study was to use ratings of perceived exertion (RPE) from the Borg (6-20) and OMNI-Leg (0-10) scales to determine the Physical Working Capacity at the Borg and OMNI thresholds ([PWC.sub.BORG] and [PWC.sub.OMNI]). [PWC.sub.BORG] and [PW.subC.oMNI] were compared with other fatigue thresholds determined from the measurement of heart rate (the Physical Working Capacity at the Heart Rate Threshold: [PWC.sub.HRT]), and oxygen consumption (the Physical Working Capacity at the Oxygen Consumption Threshold, [MATHEMATICAL NOT REPRODUCIBLE IN ASCII.]), as well as the ventilatory threshold (VT). Fifteen men and women volunteers (mean age [+ or -] SD = 22 [+ or -] 1 years) performed an incremental test to exhaustion on an electronically braked ergometer for the determination of V[O.sub.2 peak] and VT. The subjects also performed 4 randomly ordered workbouts to exhaustion at different power outputs (ranging from 60 to 206W) for the determination of [PWC.sub.BORG], [PWC.sub.OMNI], [PWC.sub.HRT], and [MATHEMATICAL EXPRESSION NOR REPRODUCIBLE IN ASCII.] The results indicated that there were no significant mean differences among the fatigue thresholds: [PWC.sub.BORG] (mean [+ or -] SD = 133 [+ or -] 37W; 67 [+ or -] 8% of V[O.sub.2 peak]), [PWC.sub.OMNI] (137 [+ or -] 44W; 68 [+ or -] 9% of V[O.sub.2] peak), [PW.sub.CHRT] (135 [+ or -] 36W; 68 [+ or -] 8% of V[O.sub.2 peak]), [MATHEMATICAL EXPRESSION NOR REPRODUCIBLE IN ASCCI.],(145 [+ or -] 41W; 72 [+ or -] 7% of V[O.sub.2 peak]) and VT (131 [+ or -] 45W; 66 [+ or -] 8% of V[O.sub.2 peak]). The results of this study indicated that the mathematical model used to estimate [PW.sub.CHRT] and [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII.], can be applied to ratings of perceived exertion to determine [PWC.sub.BORG] and [PWC.sub.OMNI] during cycle ergometry. Salient features of the [PWC.sub.BORG] and [PWC.sub.OMNI] tests are that they are simple to administer and require the use of only an RPE scale, a stopwatch, and a cycle ergometer. Furthermore, the power outputs at the [PWC.sub.BORG] and [PWC.sub.OMNI] may be useful to estimate the VT noninvasively and without the need for expired gas analysis. KEY WORDS fatigue threshold, Borg scale, OMNI-leg scale