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This investigation examined Akt-FOXO3A signaling in young women (YW) and old women (OW) before and after 12 weeks of high-intensity resistance training. Muscle biopsies were taken from the vastus lateralis before and immediately after resistance exercise (RE) in the untrained and trained states. In response to RE in YW and OW, phospho Akt Thr308 increased in untrained and trained states, with no change on Ser473 site. FOXO3A--Ser253 site was dephosphorylated in untrained state among YW and OW, and nuclear phospho-FOXO3A increased mainly in YW in trained state. In the basal state, OW displayed lower cytosolic phospho-FOXO3A before training, higher total nuclear FOXO3A, and a trend for higher nuclear-to-cytosolic FOXO3A ratio versus YW after 12 weeks. Basal level MuRF-1 and myostatin mRNA decreased in YW, while OW increased myostatin mRNA after 12-weeks. These data suggest that FOXO3A signaling and FOXO3A-related target gene expression are altered in OW and may partially explain the attenuated training adaptations previously reported in these octogenarian women. Key Words: Octogenarian--Plasticity--Forkhead--Proteolytic. doi: 10.1093/gerona/glq005

Resistance training for health is increasingly popular, yet limited research exists regarding the most appropriate and reliable methods to evaluate outcomes among nonathletic populations. The purpose of this study was to evaluate differences between multiple trials of 1 repetition maximum (1RM) strength in healthy previously untrained women (35.5 [+ or -] 2.1 years). Nineteen participants completed 3 trials of 1RM chest and leg press with at least 24 hours rest between trials. Familiarization was incorporated into trial 1 for both tests. All trials were highly reliable (intraclass correlation = 0.95). For 1RM chest press, nonsignificant strength changes between trials 1-2 and 2-3 were 1.2 [+ or -] 0.3 kg (p = 0.13) and 1.3 [+ or -] 0.4 kg (p = 0.18), respectively, while the overall increase between trials 1-3 was 2.5 [+ or -] 0.7 kg (p = 0.06). For 1 RM leg press, strength changes between trials 1-2 and 2-3 were 6.9 [+ or -] 0.6 kg (p = 0.05) and 7.3 [+ or -] 0.4 kg (p = 0.01), respectively, while the overall difference between trials 1-3 was 14.2 [+ or -] 1.0 kg (p < 0.01). In this study of untrained women, evaluation of maximal strength was significantly different between multiple repeated trials of lower-body strength but not upper-body strength. Thus, it was determined that a series of 3 1RM tests was sufficient to obtain a consistent measurement of maximal upper-body strength (chest press) but not lower-body strength (leg press). These findings may be of assistance for efficient reliable field testing of untrained women. KEY WORDS maximal strength testing, resistance exercise, rating of perceived exertion

The purpose of the present study was to investigate the acute effects of performing a heavy resistance exercise (HRE) protocol on the mechanical variables during a series of bilateral hops. In a block-randomized design, 10 strength trained men performed an HRE or a control treatment before performing 5 series of bilateral hops separated by 2 minutes of passive recovery. Each series of bilateral hops was performed for 15 seconds on a force platform with the subject hopping at a frequency of 2.0 Hz. From the vertical force trace, the vertical force during the countermovement phase of each hop, the negative displacement during the countermovement phase, and the vertical stiffness were calculated. The HRE treatment consisted of performing parallel back squats with 40, 50, 60, and 80% of each subject's 1-repetition maximum after a series of dynamic stretches. The control treatment consisted of the dynamic stretches only. No significant differences in any of the mechanical variables were reported after the 2 treatments (p > 0.05). There were no significant correlations between the absolute maximal strength values and the percent change in any of the mechanical variables after the 2 treatments. Despite the lack of significant changes reported for the group, there were some notable individual responses. It is possible that increases in vertical stiffness during bilateral hops can be achieved after an HRE protocol in certain individuals. However, practitioners should be aware of the specificity issues and the individual nature of the responses to such protocols. WORDS bilateral hopping, vertical stiffness, potentiation, heavy resistance exercises

This cross-sectional study examined aging and resistance exercise-related changes in intramuscular gene expression in younger (21.3 [+ or -] 0.6 years, 84.8 [+ or -] 6.0 kg, 26.6 [+ or -] 2.1 kg-[m.sup.2]; n = 11) and older men (67.6 [+ or -] 1.3 years, 88.7 [+ or -] 4.8 kg, 28.6 [+ or -] 1.4 kg x [m.sup.-2]; n = 13) surrounding a single bout of resistance exercise. Participants completed 3 x 10 repetitions at 80% of their 1 repetition maximum for Smith squat, leg press, and leg extension. Muscle biopsies were obtained before and 24 hours after exercise, whereas venous blood was collected before, immediately after and 24 hours after exercise. Free testosterone levels were greater in younger participants at all time points (p < 0.05), in addition to a greater increase in the younger men immediately post exercise (p < 0.01). Preexercise human growth hormone levels between age groups were similar (p > 0.05). Human growth hormone increased immediately post exercise in both groups (p < 0.05) with a greater response occurring in the younger (p < 0.001) men. Older men expressed greater levels of androgen receptor (AR) at rest (p = 0.02). A significant correlation existed between preexercise free testosterone levels basal AR gene expression (r = 0.59, p < 0.01). These data suggest that AR expression patterns may be related to circulating free testosterone levels. Although these findings do not fully unveil the genomic effects of androgen signaling and its relationship to muscle wasting conditions, these results provide a platform for future researchers seeking to employ gene therapy to remedy muscle loss. KEY WORDS aging, gene expression, muscle, hypertrophy

We determined muscle fiber type-specific hypertrophy and changes in satellite cell (SC) content following a 12-week resistance training program in 13 healthy, elderly men (72 [+ or -] 2 years). Leg strength and body composition (dual-energy X-ray absorptiometry and computed tomography) were assessed, and muscle biopsy samples were collected. Leg strength increased 25%-30% after training (p < .001). Leg lean mass and quadriceps cross-sectional area increased 6%-9% (p < .001). At baseline, mean fiber area and SC content were smaller in the Type II versus Type I muscle fibers (p < .01). Following training, Type II muscle fiber area increased from 5,438 [+ or -] 319 to 6,982 [+ or -] 503 [micro][m.sup.2] (p < .01). Type II muscle fiber SC content increased from 0.048 [+ or -] 0.003 to 0.084 [+ or -] 0.008 SCs per fiber (p < .001). No changes were observed in the Type I muscle fibers. In older adults, skeletal muscle tissue is still capable of inducing SC proliferation and differentiation, resulting in Type II muscle fiber hypertrophy. Key Words: Aging--Exercise--Muscle plasticity.

It was hypothesized that subjects receiving increased resistance in the squat exercise would demonstrate better technique and better understanding of how to perform the skill than subjects performing the exercise with no increase in resistance. Scores were recorded on the following analyses: the questionnaire analysis, which measured cognitive representation; the video analysis, which measured squat performance technique; and the 3-dimensional figure analysis, which measured the degree of similarity between the position of the model and the position of the subjects during the performance task. Ten undergraduate students were sampled, half of whom received increased resistance in the squat exercise. Admission requirements were that the subjects be men, be matched for age, body weight, and height, and have no experience in resistance training or formal instruction in proper squat technique. After measuring subjects' cognitive representation with the questionnaire, subsequent analyses were conducted to further clarify treatment effects. The second analysis involved measuring differences between the videotaped performance of the model and the videotaped performance of naive subjects. The third analysis consisted of subjects assembling a 3-dimensional wooden figure to duplicate the proper biomechanics of the expert model, which was then photographed and compared with the model's template assembly of the wooden figure. It was concluded that subjects performing the squat with increased resistance showed significant (p < 0.05) improvement in cognitive representation accuracy and performance technique compared with subjects who performed the squat with no increase in resistance. The directional hypothesis was supported. Namely, the scores of subjects receiving the treatment were predicted to be significantly greater than the scores of those who received no treatment. These data suggest that increasing the resistance in subsequent trials of the squat exercise may be a positive factor in enhancing the performance and improving the biomechanical technique of novice lifters. KEY WORDS observational learning, symbolic Coding

The main purposes of this study were 1) to describe and to compare blood lactate ([La]), heart rate (HR), and electromyographic (EMG) parameters during high-repetition training sessions (HRTSs), 2) to analyze the influence of physical fitness levels in these parameters, and, 3) to analyze the relationship between metabolic ([La]) and neuromuscular (EMG) responses during the HRTS. Fifteen healthy untrained women (21.7 [+ or -] 2.1 years) performed an HRTS called Bodypump for 1 hour, which incorporated the use of variable free weights and high repetitions in a group setting. This session involved 10 music selections (M1-M10) containing resistive exercises for different muscle groups. After music selections 2 (M2), 4 (M4), 6 (M6), 7 (M7), and 9 (M9), [La], HR, and EMG (vastus medialis [VM], vastus lateralis [VL], iliocostalis lumborum [IC], and longissimus thoracis KEY WORDS physical fitness, electromyography, physiology, fatigue

This study was designed to analyze the effects of a short-term periodized aquatic resistance program (PARP) on upper-limb maximum strength, leg muscular power, and body composition (BC) in fit young men. Twenty subjects (21.2 [+ or -] 1.17 years) were randomly assigned to an exercise or control group; 12 subjects completed the study. The aquatic exercise group (AEG; n = 7) participated in an 8-week supervised program of 3 d x [wk.sup.-1], and the control group (CG; n = 5) maintained their regular activities. The PARP consisted of a total-body resistance exercise workout using aquatic devices that increased drag force, with a cadence of movement controlled and adjusted individually for each exercise and subject. The volume and intensity of the program were increased progressively. Submaximal tests were carried out to determine the change in upper-limb maximum strength, as well as a squat-jump test to determine the change in leg muscular power. Four skinfold sites, 6 circumference sites, body weight, and stature were used to determine changes in BC. A significant increase in upper-limb maximum strength and leg muscular power was observed for the AEG. A significant increase also was noted in the circumference and muscular area of the arm, and there were significant decreases in pectoral and abdominal skinfolds. Nevertheless, the circumference, muscular area, and local fat of the lower limbs did not change. There were no significant changes in any variables in the CG. These results indicate that the PARP produces significant improvements in muscular strength, power, and fat-free mass and, thus, seems to be a very effective form of resistance exercise. KEY WORDS drag force, monitored cadence of movement, periodized

This study investigated clinic and ambulatory blood pressure (BP) responses after a single bout of low-intensity resistance exercise in normotensive subjects. Fifteen healthy subjects underwent 2 experimental sessions: control--40 minutes of seated rest, and exercise-6 resistance exercises, with 3 sets of as many repetitions as possible until moderate fatigue, with an intensity of 50% of 1 -repetition maximum (1RM). Before and for 60 minutes after interventions, clinic BP was measured by auscultatory and oscillometric methods. Postintervention ambulatory BP levels were also measured for 24 hours. In comparison with preintervention values, clinic systolic BP, as measured by the auscultatory method, did not change in the control group, but it decreased after exercise (-3.7 [+ or -] 1.6 mm Hg, p < 0.05). Diastolic and mean BP levels increased after intervention in the control group (+3.4 [+ or -] 1.0 and +3.0 [+ or -] 0.8 mm Hg, respectively, p < 0.05) and decreased in the exercise group (-3.6 [+ or -] 1.7 and 3.4 [+ or -] 1.4 mm Hg, respectively, p < 0.05). Systolic and mean oscillometric BP levels did not change after interventions either in the control or exercise sessions, whereas diastolic BP increased after intervention in the control group (+5.0 [+ or -] 1.7 mm Hg, p < 0.05) but not change after exercise. Ambulatory BP behaviors after interventions were similar in the control and exercise sessions. Significant and positive correlations were observed between preexercise values and postexercise clinic and ambulatory BP decreases. In conclusion, in the whole sample, a single bout of low-intensity resistance exercise decreased postexercise BP under clinic, but not ambulatory, conditions. However, considering individual responses, postexercise clinic and ambulatory hypotensive effects were greater in subjects with higher preexercise BP levels. KEY WORDS ambulatory blood pressure, clinic blood pressure, hypotension, strength exercise

Background. Training cessation among older adults is associated with the loss of functional ability. However, exercise programs undertaken prior to activity cessation may offer functional protection. In the present study, the residual effects of muscle power or muscle strength training were investigated following extended detraining and subsequent retraining. Methods. Thirty-eight healthy independent older adults (65-84 years) entered a 24-week detraining period subsequent to 24 weeks of training. Following detraining, participants recommenced training using either the high-velocity muscle power (HV) or muscle strength (ST) protocol, as undertaken during the initial training period, twice weekly for 12 weeks. Isometric and dynamic muscle strength, muscle power, movement velocity, muscle endurance, electromyographic activity, and the results of a battery of functional performance tasks were assessed. Results. Muscle function and functional performance increased following initial training, however, no group differences were observed. Detraining resulted in similar declines in muscle power and muscle strength for both groups (p < .05) (power, HV 17.8 [+ or -] 1.8%, ST 15.5 [+ or -] 2.2%; and strength, HV 17.1 [+ or -] 2.2%, ST 16.5 [+ or -] 1.8%), with comparable accrual following retraining. No significant changes in functional ability were observed following detraining (average change; HV 3.1 [+ or -] 3.5% and ST 2.1 [+ or -] 3.5%) or retraining. No group differences emerged in this study. Conclusion. Cessation of training resulted in only a modest loss of muscle power and strength that was recouped following 12 weeks of retraining. Importantly, training-induced gains in functional performance were preserved during detraining. The residual effects of power or strength training appear comparable, and both may be suitable exercise modes prior to a period of activity cessation to promote physical independence. Key Words: Resistance training--Functional performance--Muscle function--Detraining--Retraining.

The purpose of the present study was to examine the effect of heating and cooling the forearm muscles on renal vascular responses to ischemic isometric handgrip (IHG). It was hypothesized that heating and cooling the forearm would augment and attenuate, respectively, renal vascular responses to IHG. Renal vascular responses to IHG were studied during forearm heating at 39[degrees]C (n = 15, 26 [+ or -] 1 yr) and cooling at 26[degrees]C (n = 12, 26 [+ or -] 1 yr). For a control trial, subjects performed the experimental protocol while the forearm was normothermic (~34[degrees]C). Muscle temperature (measured by intramuscular probe) was controlled by changing the temperature of water cycling through a water-perfused sleeve. The experimental protocol was as follows: 3 min at baseline, 1 min of ischemia, ischemic IHG to fatigue, and 2 min of postexercise muscle ischemia. At rest, renal artery blood velocity (RBV; Doppler ultrasound) and renal vascular conductance (RVC = RBV/mean medal blood pressure) were not different between uormothermia and the two thermal conditions. During ischemic IHG, there were greater decreases in RBV and RVC in the heating trial. However, RBV and RVC were similar during postexercise muscle ischemia during heating and normothermia. RVC decreased less during cooling than in normothermia while the subjects performed the ischemic IHG protocol. During postexercise muscle ischemia, RVC was greater during cooling than in normothermia. These results indicate that heating augments mechanoreceptor-mediated renal vasoconstriction whereas cooling blunts metaboreceptor-mediated renal vasoconstriction. cold; heat; exercise pressor reflex; sympathetic

Background. Age-related muscle loss (sarcopenia) is a prevalent condition associated with disability and mortality. Exercise and optimal nutrition are interventions to prevent and treat sarcopenia, yet little is known, outside of protein, of the effect of common nutrition recommendations and medication use on exercise-related muscle gain. Methods. Forty-nine community-dwelling, 60- to 69-year-old men and women completed 2 weeks of nutrition education (American Dietetic Association recommendations) followed by 12 weeks of high intensity resistance exercise training (RET) with postexercise protein supplementation and 3x/wk dietary logs. Results. We observed a dose-response relationship between dietary cholesterol (from food logs) and gains in lean mass that was not affected by variability in protein intake. Serum cholesterol and the serum cholesterol lowering agent statin were also independently associated with greater increases in lean mass. Dietary cholesterol was not associated with serum cholesterol or the significant reduction in blood pressure observed, but trends were observed for altered plasm rotein. Conclusion. These data suggest that dietary and serum cholesterol contribute to the skeletal muscles' response to RET in this generally healthy older population and that some statins may improve this response.

Few studies have examined the effects of eccentric exercise-induced muscle damage on power despite power being a key performance variable in a number of sporting events. The aim of this study was to examine changes in anaerobic power (30-second Wingate Test), isometric strength of the knee extensors and flexors, muscle soreness, and plasma creatine kinase (CK) activity following downhill running. Eight men performed a 40-minute downhill (-7%) run on a treadmill, and measurements were taken on 6 occasions (2 baseline and 0.5, 24, 72, and 120 hours postrun). A second group of men (n = 5) had the measurements taken on 6 occasions without downhill running and served as a control group. A repeated measures analysis of variance revealed no significant changes in any measures across time for the control group. Following downhill running, significant (p < 0.05) decreases in strength (0.5-24 hours), and significant increases in muscle soreness (0.5-72 hours) and plasma CK activity (0.5-120 hours) were observed. A significant decrease in peak and average power (~5%) was evident only 0.5 hours postrun, and the decrease was smaller in magnitude than that of strength (~15%). These results suggest that power is less affected than strength after eccentric exercise, and the effect of reduced power on sport performance seems negligible. KEY WORDS. eccentric exercise, muscle damage, isometric strength, delayed onset muscle soreness, creatine kinase

The purpose of this study was to investigate the influence of different resistance exercise orders on the number of repetitions performed to failure and on the ratings of perceived exertion (RPE) in trained women. Twenty-three women with a minimum of 2 years of resistance training experience volunteered to participate in the study (age, 24.2 [+ or -] 4.5 years; weight, 56.9 [+ or -] 4.7 kg; height, 162.3 [+ or -] 5.9 cm; percent body fat, 18.2 [+ or -] 2.9%; body mass index, 22.2 [+ or -] 2 kg*[m.sup.-2]). Data were collected in 2 phases: (a) determination of a 1 repetition maximum (1RM) for the leg-press (LP), bench press (BP), leg extension (LE), seated machine shoulder press (SP), leg curl (LC), and seated machine triceps extension (TE); and (b) execution of 3 sets, with 2-minute rest intervals between sets and exercises, until fatigue using 80% of 1RM in 2 exercise sequences of the exact opposite order--Sequence A: BP, SP, TE, LP, LE, and LC, and Sequence B: LC, LE, LP, TE, SP, and BP. The RPE (Borg CR-10) was accessed immediately after each sequence and analyzed using a Wilcoxon test. A 2-way analysis of variance with repeated measurements, followed by a post hoc Fisher least significant difference test where indicated was used to analyze the number of repetitions per set of each exercise during the 2 sequences. The RPE was not significantly different between the sequences. The mean number of repetitions per set was always less when an exercise was performed later in the exercise sequence. The data indicate that in trained women, performance of both large- and small-muscle group exercises is affected by exercise sequence. KEY WORDS. strength training, performance, Borg scale, strength

Enhancing the acute quality of the resistance training stimulus is the goal of many research and applied professionals. To that end, many methods have been proposed and a variety of training strategies and ergogenic supplements have been investigated. Postactivation potentiation is one phenomenon that has been frequently examined, offering some promise in this regard. Though never previously applied in the strength and conditioning profession, dental research on jaw clenching, studies examining the Jendrassik maneuver and remote voluntary contractions and research on motor overflow together make a compelling case for the existence of a concurrent activation potentiation phenomenon and the acute ergogenic advantage associated with the simultaneous activation of muscles other than the prime mover or synergists. Evidence demonstrates that this advantage is accrued via activation of the H reflex and through cortical overflow. Ultimately, through research and practical application, athletes may be taught to optimize the type, timing, and magnitude of remote muscle actions in order to gain an ergogenic advantage and increase the acute response of the prime movers. This strategy may be especially useful during the most difficult portion of a resistance training repetition and during the most difficult repetitions of a resistance training set. KEY WORDS. Jendrassik maneuver, remote voluntary contractions, motor overflow, strength

The purpose of this study was to assess the effect of stable vs. unstable conditions on force output and muscle activity during an isometric squat. Nine men involved in recreational resistance training participated in the investigation by completing a single testing session. Within this session subjects performed isometric squats either while standing directly on the force plate (stable condition, S) or while standing on inflatable balls placed on top of the force plate (unstable condition, U). Electromyography (EMG) was recorded during both conditions from the vastus lateralis (VL), vastus medialis (VM), biceps femoris (BF), and medial gastrocnemius (G) muscles. Results indicated peak force (PF) and rate of force development (RFD) were significantly lower, 45.6% and 40.5% respectively, in the U vs. S condition (p [less than or equal to] 0.05). Average integrated EMG values for the VL and VM were significantly higher in the S vs. U condition. VL and VM muscle activity was 37.3% and 34.4% less in U in comparison to S. No significant differences were observed in muscle activity of the BF or G between U and S. The primary finding in this investigation is that isometric squatting in an unstable condition significantly reduces peak force, rate of force development, and agonist muscle activity with no change in antagonist or synergist muscle activity. In terms of providing a stimulus for strength gain no discernable benefit of performing a resistance exercise in an unstable condition was observed in the current study. KEY WORDS. instability, strength, power, resistance training

Previous work from our laboratory demonstrated that isometric handgrip (IHG) training improved local, endothelium-dependent vasodilation in medicated hypertensives [McGowan CL (PhD Thesis), 2006; McGowan et al. Physiologist 47: 285, 2004]. We investigated whether changes in the capacity of smooth muscle to dilate (regardless of endothelial factors) influenced this training-induced change, and we examined the acute vascular responses to a single bout of IHG. Seventeen subjects performed four 2-min unilateral IHG contractions at 30% of maximal voluntary effort, three times a week for 8 wk. Pre- and posttraining, brachial artery flow-mediated dilation (FMD, an index of endothelium-dependent vasodilation) and nitroglycerin-mediated maximal vasodilation (an index of endothelium-independent vasodilation) were measured in the exercised arm by using ultrasound before and immediately after acute IHG exercise. IHG training resulted in improved resting brachial FMD (P < 0.01) and no change in nitroglycerin-mediated maximal vasodilation. Pre- and posttraining, brachial artery FMD decreased following an acute bout of IHG exercise (normalized to peak shear rate, pre-, before IHG exercise: 0.01 [+ or -] 0.002, after IHG exercise: 0.008 [+ or -] 0.002%/[s.sup.-l]; post-, before IHG exercise: 0.020 [+ or -] 0.003, after IHG exercise: 0.010 [+ or -] 0.003%/[s.sup.-1]; p < 0.01). Posttraining, resting brachial artery FMD improved yet nitroglycerin-mediated maximal vasodilation was unchanged in persons medicated for hypertension. This suggests that the training-induced improvements in the resting brachial artery FMD were not due to underlying changes in the forearm vasculature. Acute IHG exercise attenuated brachial artery FMD, and although this impairment may be interpreted as hazardous to medicated hypertensives with already dysfunctional endothelium, the effects appear transient as repeated exposure to the IHG stimulus improved resting endothelium-dependent vasodilation. acute exercise; isometric training; flow-mediated dilation; blood flow

According to the parallel force unit model (PFUM) the programming of an isometric force pulse requires the specification of the number of force units and force unit duration. The programming of a force pulse with minimal time-to-peak force is an exception, however, as force unit duration is limited by the minimal possible value, which should be easier to adjust than larger force unit durations. Therefore, the duration of the programming process should be shorter for these force pulses and hence should result in shorter reaction time (RT). Four experiments assessed this prediction using a response precueing procedure. In each experiment the participants produced isometric flexions with their left or right index finger, and time-to-peak force was manipulated within a block. The results are consistent with the predictions of PFUM. The results, however, are at variance with alternative accounts which assume that RT depends primarily on response duration or rate of force production.

The effect of rest intervals on knee-extension torque production is compared. A 120-second rest between repetitions is recommended when using neuromuscular electrical simulations (NMES) in early rehabilitation because force decline across repetitions with 30-second rest during NMES is greater than maximum voluntary isometric contraction (MVIC).

The purpose of this study was to compare the effect of 3 different rest intervals on the sustainability of squat and bench press repetitions over 5 consecutive sets performed with a 15 repetition maximum (RM)-load. Fifteen college-age men with previous resistance training experience were tested weekly over a period of 3 weeks. During each testing session, 5 consecutive sets of the squat and the bench press were performed with a 30-second, 1-minute, or 2-minute rest interval between sets. For each exercise, significant declines in repetitions occurred between the first and the fifth sets (p = 0.000). For the squat, a significant difference in the ability to sustain repetitions occurred between the 30-second and 2-minute rest condition Cp = 0.003). However, differences were not significant between the 30-second and l-minute rest conditions (p = 0.986) and between the l-minute and 2-minute rest conditions (p = 0.042). For the bench press, significant differences in the ability to sustain repetitions occurred between the 30-second and 2-minute rest conditions (p = 0.000) and between the 1-minute and 2-minute rest conditions (p = 0.000). However, differences were not significant between the 30-second and 1-minute rest conditions (p = 0.019). For each exercise, the number of repetitions completed on the first set was not sustained over subsequent sets, irrespective of the rest condition. These results suggest that when short rest intervals are used to develop muscular endurance, the intensity should be lowered over subsequent sets to sustain repetitions within the range conducive to this training goal. KEY WORDS. recovery, muscular endurance, fatigue, performance, volume

This study examined the construct validity of the Adult OMNI Perceived Exertion Scale for Resistance Exercise (OMNI-RES). Forty (20 men and 20 women) subjects performed 1 repetition of the knee extension exercise at 40, 50, 60, 70, 80, and 90% of the 1 repetition maximum. Active muscle and overall body ratings of perceived exertion (RPE) were collected from the Borg 15-category RPE scale and the OMNI-RES immediately following each repetition. Construct validity was established by correlating RPE from the OMNI-RES with RPE from the Borg RPE scale using regression analysis. The results indicated a positive and linear relationship between RPE from the OMNI-RES and RPE from the Borg scale for both men and women. Validity coefficients ranged from r = 0.94 to 0.97. The high level of construct validity indicates that the OMNI-RES measures the same properties of exertion as the Borg RPE scale during resistance exercise and suggests that the 2 scales can be used interchangeably during resistance exercise. KEY WORDS. RPE, gender, perceived exertion

Sarcopenia refers to the gradual decline in muscle mass and quality noted with advancing age. There is growing evidence linking sarcopenia to functional disability, falls, decreased bone density, glucose intolerance, and decreased heat and cold tolerance in older adults. Factors implicated in the etiology of sarcopenia include decreased physical activity, malnutrition, increased cytokine activity, oxidative stress, and abnormalities in growth hormone and sex steroid axes. At present, progressive resistance training is the best intervention shown to slow down or reverse this condition. Preliminary studies show that the utilization of several trophic factors, notably testosterone and DHEA, may have a salutary effect on muscle mass and/or strength in older adults. More research is needed, however, before drawing definite conclusion as to the clinical utility of these substances in the management of sarcopenia. Key Words: sarcopenia, frailty, muscle, aging

In order to compare the cardiovascular and energy expenditure demands of 'Super Slow' (SST) and traditional (TT) resistance training 7 resistance-trained young men (24.3 [+ or -] 3.8 years) had energy expenditure (using indirect calorimetry) and heart rate evaluated during and for 15 minutes after a workout on separate days. Blood lactate levels were also evaluated before and after each intervention. Resting energy expenditure was evaluated in a fasted state using a ventilated canopy prior to any. exercise stimulus and 21 to 22 hours after the SST and TT. V[O.sub.2] and average heart rate were both significantly higher during the TT than during the SST. The net V[O.sub.2] was also significantly higher during the 15 minutes recovery; however, average heart rate was not significantly different between the 2 groups. Total net energy expenditure from oxidative processes was 45% higher for the TT intervention (TT = 155 [+ or -] 28 kcal, and SST = 107 [+ or -] 20 kcal). The significant postexercise lactate difference was almost 2 times greater following the TT than after the SST (TT = 7.9 [+ or -] 1.7 mmol*[L.sup.-1]*[min.sup.-1] and SST = 4.0 [+ or -] 2.0 mmol*[L.sup.-1]*[min.sup.-1]). Finally, adding the estimated energy expenditure, of the blood lactate to the net energy expenditure from the V[O.sub.2] produced a significant difference that is over 48% greater for the TT intervention (TT = 172 [+ or -] 29 kcal*[min.sup.-1] and SST = 116 [+ or -] 22 kcal*[min.sup.-1]). No significant repeated measures analysis main effect was found for either resting energy expenditure or respiratory exchange ratio. The metabolic and cardiovascular stimuli were low with SST. Traditional resistance training increases energy expenditure more than SST does and thus may be more beneficial for body weight control. Key Words: energy expenditure, strength training, lactate

Issues concerning the effect of a high-carbohydrate diet on resistance exercise performance during energy restriction are discussed. A group of 22 resistance-trained men was assigned to either carbohydrate, control, or placebo prior to testing, and carbohydrate prior to a resistance exercise but done in negative energy balance state did not affect performance or result in evidence of muscle damage.