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J Strength Cond Res 24(1): 235-243, 2010--The purpose of the study was to determine how manipulation of peripheral blood flow during resistance exercise using a light load affected perception and physiological measures compared with moderate load resistance exercise and a control trial. Seven subjects performed a 3 (session) by 2 (biceps curls and calf extensions) within-subjects study that was randomized and counterbalanced across 3 weeks. The 3 sessions included (a) light resistance exercise (3 sets to failure) at 30% of 1 repetition maximum (1RM) with partial occlusion (LRO), (b) moderate resistance at 70% of 1RM with no occlusion (MR), and (c) partial occlusion without exercise (OO). Ratings of perceived exertion (RPE), pain, and heart rate were assessed immediately after each set, whereas blood samples were taken before, immediately after, and 15 minutes after exercise. Results demonstrated that RPE and pain were lower in the OO condition than that in the MR and LRO conditions for biceps curls and calf extensions, Fs(2,24) = 22.75, 20.86, ps < 0.0001 and Fs(2,24) = 18.95, 24.52, ps < 0.01 ; however, no significant differences were noted between MR and LRO conditions. Heart rate was significantly higher for the LRO condition when compared with the MR trial, F(2,18) 20.1 2, p < 0.001. Results suggest that when partial vascular occlusion with a light load was applied, both pain and effort sense were altered to a similar degree as moderate loads but no occlusion. The practical application of results were that individuals may be better able to tolerate perceptual change at low loads with partial occlusion because joint stress may be minimized while local muscle metabolic demands increase, making resistance training maximally effective and minimally stressful on joints. Perceptual tracking of effort and pain may aid coaches who attempt this protocol. KEY WORDS lactate, heart rate, exertion, hurt, perception

This study was designed to examine the effect of self-reported, stressful life events on strength gains after 12 weeks of resistance training. Participants were 135 undergraduates enrolled in weight training classes that met for 1.5 hours, two times per week. After a 2-week period to become familiar with weight training, participants completed the college version of the Adolescent Perceived Events Scale (APES), the Social Support Inventory, and one-repetition maximal lifts (1 RM) for the bench press and squat. Maximal lifts were repeated after 12 weeks of training. Median splits for stress and social support were used to form groups. Results indicated that the low stress participants experienced a significantly greater increase in bench press and squat than their high stress counterparts. Strength gains were, however, unrelated to social support scores in either the low or high stress group. High life stress may lessen a person's ability to adapt to weight training. It may benefit coaches to monitor their athletes' stress both within and outside the training setting to maximize their recovery and adaptation. KEY WORDS one-repetition max, muscular hypertrophy, social support

Previous research has shown that individuals self-select loads for resistance training that falls below the accepted threshold for overload and do not lift to volitional fatigue. The purpose of this study was to determine the effects of a resistance training learning trial on self-selected resistance training load. A control group (5 women, 3 men) and a learning group of (4 women, 4 men) novice lifters were recruited. The control group (CG) received an orientation to selected strength machines (seated bench, leg extension, back row, biceps curl, triceps extension, shoulder press). On a subsequent training day, CG selfselected a training load, while blinded to the actual loads. The learning group (LG) received an initial orientation and also was tested for estimated 1 repetition maximum (1 RM) for the seated bench press. On a subsequent day, the LG completed 2 sets of the seated bench press at 75% of estimated 1RM and were encouraged to lift until failure. On a third day, LG subjects completed a self-selected trial identical to that of the CG. Both groups were assessed for estimated 1 RM for each exercise on a separate day following all trials. Comparisons between CG and LG were made using independent-means t tests and adjusted using Bonferroni's equation (p < 0.01). While subjects selected a bench press load that was 21% greater for LG (63.4 [+ or -] 6.4% 1RM) compared to the CG (50.3 [+ or -] 12.0%), there was no statistical significance. There were no significant differences in self-selected load for any of the other exercises. There were also no significant differences for number of repetitions or rate of perceived exertion between groups. We conclude that a learning trial of the bench press exercise to increase self-selected workload is not enough to change load self-selection. KEY WORDS rate of perceived exertion, weight training, self-regulated exercise

This study examined the predictive utility of self efficacy and three types of outcome expectations (physical outcomes, social outcomes, and self-evaluative outcomes) on students' behavioral intentions and actual behaviors in a beginning weight training class. A total of 137 participants (62 men, 75 women: [M.sub.age]-21.4 yr., SD=2.0) completed questionnaires assessing beliefs and intentions toward weight training. Attendance and workout log entries were used as a measure of actual behaviors. Regression analyses indicated that physical outcome expectations and self-efficacy emerged as significant predictors of students' behavioral intentions and actual behaviors. Findings of this study were interpreted from self-efficacy theory.

Controversy exists concerning the efficacy and safety of creatine supplementation. The present study used a cross-sectional design to examine social cognitive predictors of creatine use versus non-use among 148 male, undergraduate, recreational resistance trainers. Seventy participants (47.3%) reported creatine use. Creatine users had higher self-efficacy for resistance-training with creatine, t (146) = 4.98, p < .001, higher positive outcome expectancies for improved workout performance, t (146) = 2.37, p - .019, and lower negative outcome expectancies for creatine use. t (146) = 4.90, p < .001. No significant differences were found for self-efficacy for resistance training without creatine or negative outcome expectancies for improved workout performance. Logistic regression analysis revealed that social cognitive variables accounted for 25% of the variance in creatine use. The results lay the groundwork for the understanding of performance enhancing dietary supplement use from a theoretical, social cognitive perspective., Creatine is one of the most popular performance enhancing supplements among college students (Williams & Anderson, 2000), and has received recent attention from popular media sources (Bamberger, 1998; Schrof, 1998; [...]

This study investigated the reliability of the session rating of perceived exertion (RPE) scale to quantify exercise intensity during high-intensity (H), moderate-intensity (M), and low-intensity (L) resistance training. Nine men (24.7 [+ or -] 3.8 years) and 10 women (22.1 [+ or -] 2.6 years) performed each intensity twice. Each protocol consisted of 5 exercises: back squat, bench press, overhead press, biceps curl, and triceps pushdown. The H consisted of 1 set of 4-5 repetitions at 90% of the subject's 1 repetition maximum (1RM). The M consisted of 1 set of 10 repetitions at 70% 1RM, and the L consisted of 1 set of 15 repetitions at 50% 1RM. RPE was measured following the completion of each set and 30 minutes postexercise (session RPE). Session RPE was higher for the H than M and L exercise bouts (p [less than or equal to] 0.05). Performing fewer repetitions at a higher intensity was perceived to be more difficult than performing more repetitions at a lower intensity. The intraclass correlation coefficient for the session RPE was 0.88. The session RPE is a reliable method to quantify various intensities of resistance training. KEY WORDS. strength training, Borg CR-10 scale, reliability

The purpose of the present study was to examine the influence of direct supervision on muscular strength, power, and running speed during 12 weeks of resistance training in young rugby league players. Two matched groups of young (16.7 [+ or -] 1.1 years [mean [+ or - SD]), talented rugby league players completed the same periodized resistance-training program in either a supervised (SUP) (N = 21) or an unsupervised (UNSUP) (N = 21) environment. Measures of 3 repetition maximum (3RM) bench press, 3RM squat, maximal chin-ups, vertical jump, 10- and 20-m sprints, and body mass were completed pretest (week 0), midtest (week 6), and posttest (week 12) training program. Results show that 12 weeks of periodized resistance training resulted in an increased body mass, 3RM bench press, 3RM squat, maximum number of chin-ups, vertical jump height, and 10- and 20-m sprint performance in both groups (p < 0.05). The SUP group completed significantly more training sessions, which were significantly correlated to strength increases for 3RM bench press and squat (p < 0.05). Furthermore, the SUP group significantly increased 3RM squat strength (at 6 and 12 weeks) and 3RM bench press strength (12 weeks) when compared to the UNSUP group (p < 0.05). Finally, the percent increase in the 3RM bench press, 3RM squat, and chin-[up.sub.max] was also significantly greater in the SUP group than in the UNSUP group (p < 0.05). These findings show that the direct supervision of resistance training in young athletes results in greater training adherence and increased strength gains than does unsupervised training. KEY WORDS. strength coaching, young athletes, strength training

The purpose of this study was to determine the intensity of self-selected weightlifting exercise in untrained men and women. Thirteen men (age = 19.5 [+ or -] 1.9, height = 70.0 [+ or -] 2.4 in., weight = 174 [+ or -] 20.1 lb, % fat = 14.3 [+ or -] 6.7) and 17 women (age = 18.7 [+ or -] 1.0, height = 64.9 [+ or -] 2.3 in., weight = 135.4 [+ or -] 22.8 lb, % fat = 23.4 [+ or -] 4.7) who were novice lifters completed seated bench press, leg extension, seated back row, military press, and biceps curl. Following self-selection trials, subjects' 1 repetition maximum (1RM) was assessed for each lift. Results showed that for both genders, self-selected loads were all below 60% 1RM. All lift intensities were similar for men and women (range = 42-57% 1RM). Repetitions completed and rating of perceived exertion responses were not different between gender. Results show that subjects do not select a lifting intensity sufficient to induce hypertrophic responses and subsequent strength increases. KEY WORDS. exercise prescription, strength training, % 1RM

Functional training is considered to be training that attempts to mimic the specific physiological demands of real-life activities. Most approaches to functional training, though, omit important factors that contribute to physiological and neuromotor adaptations. Cognitive factors related to sports influence physiological performance, and subsequently, physiological and neuromotor adaptations. We present a rationale and a theoretical framework by which to create effective functional training methods that incorporate cognitive factors. This framework draws upon recent developments and strong empirical evidence in the areas of dynamic systems theory, perceptual skills training, and motor learning/control. Emphasized within rigorous physical training are practice-related techniques and motor-learning strategies. In particular, mental effort, attention, and intention manipulated in a discovery-learning paradigm provide a framework for functional strength and power training. This framework is suggested to help maximize sport-specific physiological adaptations, and subsequently, sports performance. Key Words: discovery learning, athletics, performance, practice, cognition, perception

Responses to life stressors are associated with negative behaviors that may increase risk for illness and injury. The effect of high intensity exercise in reducing reactivity to psychological stress has been well documented among older people. The purpose of this study was to ascertain the effect of weight-training versus aerobic dance on psychological stress in college students. 45 students participated in a weight-training course, 35 students participated in aerobic dance classes, and 34 students served as a control group. The Survey of Recent Life Experiences was used to appraise stressfulness of current experiences before and after exercise intervention. On immediate retest after 8 wk. of weight-training perceived stress was significantly reduced when compared with an 8-wk. aerobic dance program, but there were no significant differences between the control group and the weight-training group or the aerobic dance group. These results suggest that a regular routine of low intensity exercise such as weight-training may reduce perceived stress on an immediate test.

This study examined the effects of a special curriculum designed to facilitate generalization of self-efficacy from weight-training exercises to activities of daily living (ADL) among a sample of adults with spinal injuries. Participants (N = 17) were assigned to 1 of 3 groups: (a) a weight-training instruction and self-efficacy generalization group; (b) a weight-training instruction only group; or (c) a control group. The 2 groups that received weight-training instruction received 6 weight-training lessons. The group that also received the self-efficacy generalization curriculum was exposed to techniques designed to generalize self-efficacy. Participants in the group exposed to the self-efficacy generalization curriculum experienced a significantly greater generalization of self-efficacy than did those who received weight-training instruction only and those in the control group.

Aerobic exercise was found to be an effective mood-regulating behavior, but this does not extend to resistance exercise. In a study, 40 males were randomly assigned to resistance exercise or placebo activity after having a positive, negative or neutral mood induced. Resistance exercise produced an immediate, but short-lived, increase in negative mood.

Students (39 men and 27 women) from a southern university, who were enrolled in a 14-wk. introductory weight-training course, were administered a 20-item body-image questionnaire and subsequently underwent skinfold measurements to assess percent body fat. Mean scores were correlated with percent body fat. For men, women, and both sexes combined correlations were significant and inverse (rs = -.68, -.41, -.66, respectively). Body image as measured was inversely related to percent body fat among these college students. Researchers should examine how dietary and exercise-induced changes in adiposity (pre-post design) influence scores on body image.

This study empirically assessed the effect weight training has on the accuracy of free-throw shots immediately following a weight-training session. On alternating days of the week for eight weeks, 14 members of a women's varsity intercollegiate basketball team engaged in a weight-training program and an aerobics exercise program. Each day immediately following the conditioning, the players shot two sets of 10 free throws. Analysis indicated no significant difference in free-throw shooting accuracy as a function of weight training when compared to the aerobic exercise, suggesting that the immediate effects of weight training are no more detrimental or beneficial for free-throw shooting than aerobic exercise.

27 college students participated in an advanced weight-training course while a control group of 30 completed a physical education major theory course. Both groups were administered the Rosenberg Self-esteem Scale and the Secord and Jourard Body-cathexis Scale prior to and at the conclusion of a 16-wk. field experiment. The weight-training subjects had significantly higher self-esteem and body-cathexis scores than the control group which were attributed, in part, to significant improvement in their body composition, maximal strength, and strength endurance scores. These data support the contention that global self-esteem is a multidimensional construct responsive to positive changes in the physical self.

Research examining the relationship between beta-endorphin immunoreactivity and affect has resulted in equivocal findings. To examine this relationship further, 10 male and 10 female college-age students participated in a controlled free-weight exercise session. Blood plasma samples were procured both prior to and following the exercise bout and beta-endorphin levels were determined by immunoassay. Analysis indicated that plasma beta-endorphin levels following exercise were significantly decreased from pre-exercise levels. Pearson correlations showed no significant relationship between pre- or postexercise plasma beta-endorphins and either total mood disturbance or Profile of Mood States subscores. The data support previous failure of resistance exercise to produce an increase in beta-endorphin immunoreactivity as well as the lack of a significant relationship between affect and the beta-endorphin response to exercise.