Daniel M. Landers

• Ph.D. Degree
• Professor at Arizona State University

Female Ss (N=80) observed either a teacher or a peer model (M) demonstrate a motor task with either high or low performance ability. The effects’ of viewing these live performances on S’s subsequent motor performances were examined. After the observation of M, S’s performance in the presence or absence of the observed M was investigated. A Control...

Schachter’s hypothesis that first-borns are more vulnerable than later-boms to the interfering effects of stress was experimentally tested by comparing the tracking performance of 50 first-born and 72 later-born Ss exposed to a low, moderate, or high threat of physical-harm condition. Questionnaire responses of Ss’ perceived stress and Ss’ heart ra...

This study examined Easterbrook's (1959) hypothesis that performance on a primary task would improve or at least be maintained with increased levels of arousal, while performance on a secondary task would decrease. To test this hypothesis, the performance of 20 collegiate rifle shooters (10 experienced, 10 inexperienced) on a primary target shootin...

This study examined the physical, psychological and perceptual/visual variables related to elite archers' shooting performance. Complete data on 62 variables were obtained on male (n = 44) and female (n = 35) archers, who were tested during the years 1982-1984. In order to reduce the number of variables, only those that correlated significantly wit...

Research has revealed that exercise is effective for reducing symptoms of depression and anxiety. The mechanisms by which these reductions occur, however, have not been widely studied. To examine several potential theories, a prospective, randomized, 7-week exercise intervention was conducted. Untrained participants were randomly assigned to an aer...

The s allele serotonin transporter polymorphic region (5-HTTLPR) is associated with a number of physiological mechanisms that may increase the risk of elevated depressive symptoms. However, reports of a relationship between serotonin transporter polymorphic region (5-HTTLPR) genotype and depressive symptoms have thus far been inconclusive. This het...

Exercise is effective in the alleviation of depressive symptoms and may have physiological effects similar to those of selective serotonin reuptake inhibitors (SSRI). Recent research has identified the difference in treatment effects across genetic polymorphisms of the serotonin transporter polymorphic region (5-HTTLPR), in which the l allele has b...

Several meta-analyses examining the effects of exercise on depression have been criticized for including studies of poor methodological integrity. More recent meta-analyses addressed the most common criticism by including only randomized control trials; however, these analyses suffer from incomplete literature searches and lack of moderating variab...

Several meta-analyses examining the effects of exercise on depression have been criticized for including studies of poor methodological integrity. More recent meta-analyses addressed the most common criticism by including only randomized control trials; however, these analyses suffer from incomplete literature searches and lack of moderating variab...

A meta-analysis was conducted to examine the effects of exercise on anxiety. Because previous meta-analyses in the area included studies of varying quality, only randomized, controlled trials were included in the present analysis. Results from 49 studies show an overall effect size of -0.48, indicating larger reductions in anxiety among exercise gr...

This study examined cardiovascular responses as a function of time following exercise in which participants were exposed to a laboratory stressor. Ninety (42 women) young (18-35 years old) nonsmoking normotensive participants engaged in 30 min of high and low intensity (75-80% and 50-55% VO(2) max) aerobic exercise and a sedentary control condition...

Research has demonstrated the anxiolytic and affective changes following resistance exercise. However, several studies have allowed the participants to leave the testing facility and return at a later time to complete psychological assessments. This weakens internal validity, making it impossible to interpret findings as due to exercise per se. To...

Although many researchers have examined the effects of imagery and/or modelling interventions, it is unclear which of the two interventions is more effective. In two experiments, novice learners assessed over multiple trials of a free weight squat lifting or a stabilometer balancing task were given modelling, imagery, a combination of modelling and...

Data were obtained from elite rifle marksmen during baseline and performance conditions (prior to trigger pull) to examine electroencephalographic (EEC) alpha and heart rate (Ilk) patterning. The results were discussed in terms of “response intention” because a trend was found in HR patterning during performance which paralleled that associated wit...

A longstanding research question in the sport psychology literature has been whether a given amount of mental practice prior to performing a motor skill will enhance one's subsequent performance. The research literature, however, has not provided any clear-cut answers to this question and this has prompted the present, more comprehensive review of...

Many studies have been conducted to test the potentially beneficial effects of physical activity on cognition. The results of meta-analytic reviews of this literature suggest that there is a positive association between participation in physical activity and cognitive performance. The design of past research demonstrates the tacit assumption that c...

The mediating effect of peripheral narrowing in the negative life event stress (N-LES)/athletic injury relationship was investigated. LES and other psychosocial variables were measured, and peripheral vision was assessed in nonstressful (practice day) and stressful (game day) sport situations. Results showed that total LES, N-LES, and psychological...

The purpose of this study was to examine the dose-response gradient of exercise-induced affective change and the role of the stress response as a contributing mechanism. Male and female participants (N = 31) completed three different resistance training protocols (40%, 70%, and 100% of 10-repetition maximum [RM]) and a no-treatment control conditio...

Anxiety involves complex, incompletely understood interactions of genomic, environmental, and experience-derived factors, and is currently being measured by psychological criteria. Here, we report previously nonperceived interrelationships between expression variations and nucleotide polymorphisms of the chromosome 7q21-22 acetylcholinesterase-para...

The deaths of three intercollegiate wrestlers in 1997 prompted the NCAA and governing bodies that oversee high school sports to adopt new policies prohibiting unsafe weight loss practices. Similar policies have not yet been adopted for international style wrestling, a style that attracts thousands of youth once the regulated scholastic season is ov...

Psychological well-being has been generally associated with vigorous aerobic activity and structured aerobic activity in adolescents and children. Low-income children are at greater risk than the general population for experiencing high environmental stress and increased mental health problems. This study investigated the effects of a structured ph...

Until recently, the traditional Inverted-U hypothesis had been the primary model used by sport psychologists to describe the arousal-performance relationship. However, many sport psychology researchers have challenged this relationship, and the current trend is a shift toward a more "multidimensional" view of arousal-anxiety and its effects on perf...

The purpose of this investigation was to examine the effects of the presence of an audience and competition on maximal weight lifting performance. Thirty-two recreationally trained participants (15 men, 17 women; 21 +/- 2.5 years) performed a 1 repetition maximum (1 RM) bench press during 3 different situations (coaction, competitive coaction, and...

Previous research has only examined perceptual deficits that are hypothesized in a model of stress and injury under laboratory-induced stress conditions. The generalizability of findings from such induced-stress conditions is limited beyond the laboratory. The current research examined the influence of life-event stress and hardiness on peripheral...

The cross-sectional relationship between exercise training history and performance on a fluid intelligence test was examined. In addition, openness to experience was included as a potential trait-based contributor to predicting cognitive performance. Results supported past literature demonstrating that aerobically trained or active participants per...

Based on inflow explanations, the predictions related to EMG activity during imagery of a dumbbell and manipulandum curl were that EMG activity: (a) increases, relative to baseline, in both the biceps and triceps of the active arm; (b) is localized to muscles used in executing the real movement; and (c) mirrors the pattern of activity observed duri...

Recent research has demonstrated transient affective changes and impairment of short-term memory in college wrestlers as a result of rapid weight loss (RWL) of at least 5% body weight prior to competition. This study examined the effects of RWL on cognition and affect in high school wrestlers. Wrestlers were considered to be engaging in RWL if they...

Examined the influence of procedural and moderating variables on the efficacy of mental practice (MP) performed prior to motor task (golf putting) execution. Procedural variables were MP script and number of MP repetitions; gender and skill were possible moderating variables. Results for Exp 1 (120 novice and intermediate golfers) show that mentall...

This meta-analysis examined the exercise-mood relationship in older adults. 158 effect sizes (ESs) from 32 studies were grouped into experimental-versus-control, gains, and correlational ESs. Each study was coded for moderator variables related to descriptive, design, participant, exercise, and mood assessment characteristics. Experimental-versus-c...

The present study focused on an examination of competitive shooters' aiming process during a rifle shooting task. The barrel movements of the rifle, as detected by a laser system during the last 1000-ms time period preceding the triggering, were recorded from six elite and six pre-elite shooters. Electrocortical slow potentials (SPs) from frontal (...

Several recent studies have pointed out that the weight loss techniques used by wrestlers to make weight are similar to the behavior of bulimics. The purpose of this study was to determine whether an increased risk of bulimia nervosa existed for a group of junior high and high school wrestlers. Wrestlers (N = 85) completed the Eating Disorder Inven...

The effect of exercise on negative affect has been examined in hundreds of studies. However, the effect of exercise on diagnosed clinical depression has received far less attention. Furthermore, poor methodological techniques predominate and results have been conflicting. A meta-analysis was conducted to investigate the effect of exercise on clinic...

Past studies have shown that electroencephalographic alpha activity increases as people learn to perform a novel motor task. Additionally, it has been suggested that motor performance and learning decline as people age beyond 60 years, and it has been hypothesized that physical fitness may attenuate this decline through its impact on the cerebral e...

Nearly 200 studies have examined the impact that either acute or long-term exercise has upon cognition. Subsets of these studies have been reviewed using the traditional narrative method, and the common conclusion has been that the results are mixed. Therefore, a more comprehensive review is needed that includes all available studies and that provi...

The primary purpose of this study was to examine differences in performance on fluid and crystallized intelligence tasks as a function of age and fitness. A secondary purpose was to examine the influence of age and fitness on the beneficial effects that practice has on both performance and retention on these tasks. Fitness was assessed in 41 older...

The primary purpose of this study was to examine differences in performance on fluid and crystallized intelligence tasks as a function of age and fitness. A secondary purpose was to examine the influence of age and fitness on the beneficial effects that practice has on both performance and retention on these tasks. Fitness was assessed in 41 older...

Exercise science researchers are familiar with the use of parametric tests to detect significant differences among treatment groups. However, in planning research a question asked with increasing frequency is, "How many participants are needed to detect real and meaningful differences among groups?" In this paper, we provide an overview of the use...

HIGHLIGHT "We now have evidence to support the claim that exercise is related to positive mental health as indicated by relief in sympotoms of depression and anxiety." A NOTE FROM THE EDITORS Mental health as discussed in this paper by Dr. Daniel Landers, a leading authority on this topic, focuses on conditions sometimes considered to be illness st...

This study was designed to examine changes in EEG activity associated with the learning of a novel task. Right-handed adults (N = 61) were randomly assigned to experimental and control groups. Subjects'EEG was recorded at 10 sites. Subjects' performance was assessed using 8-s trials on a mirror star trace. On the acquisition day, the experimental s...

Studies attempting to ascertain the effects of acute and chronic exercise on measures of sleep have yielded conflicting results and interpretations. Methodological differences among studies may explain this lack of consensus; however, small sample sizes and subsequently low statistical power may also have contributed. In an attempt to resolve these...