Vertical Jumping Performance: Recording the Effects of Proprioceptive Neuromuscular Facilitation Stretching at Different Plantar Flexor Lengths.

INTRODUCTION: Flexibility seems to be an essential part of both the training and rehabilitation processes. Several stretching techniques have been used to improve the range of motion (ROM) of the joints with the proprioceptive neuromuscular facilitation (PNF) method being the most effective one. Although plantar flexors are ideal to compare the acute effects of synergistic muscle groups on performance, it is not clear whether the PNF stretch at different muscle lengths could result in different alterations. MATERIAL AND METHODS: Sixteen male students randomly performed 2 levels of stretching (PNF with bended knees, or PNFshort, and with extended knee, or PNFlong) and 3 types of jumps, separated by 48 hours (7 sessions in total). Jumping parameters were recorded by a force plate, and the final jumping height (H) and ground reaction forces (Fz) were analyzed. Furthermore, the ROM of the ankle joint was recorded before, right after, and 15 minutes after the stretches.  Results: The ankle joint's ROM joint was increased after both interventions. No significant changes were found in the jumping height of all jumps. The Fz, during the squat jump (SJ) and countermovement jump (CMJ), were increased after PNFshort. Similarly, a significant increase was found in Fz in drop jumps (DJ) right after the PNFshort. CONCLUSION: Our findings demonstrated that PNF stretches of different lengths could potentially alter the stretch-shortening cycle's performance, possibly leading to a non-optimal muscle-tendon interaction.

Ankle-Specific Training Does Not Alter Drop Jumping Biomechanics Despite Increased Plantar Flexor Strength and Jumping Performance.

INTRODUCTION: Power plays a crucial role in determining an athlete's final performance, as it signifies the ability to rapidly generate force. The plantar flexor muscles have a crucial role in producing the necessary power. The plantar flexor muscles are important in explosive sports movements due to their ability to generate substantial force quickly during the propulsion phase and facilitate efficient energy transfer through the joints. This study aimed to investigate the effects of specific plantar flexor training on drop jumping (DJ) biomechanics, muscle activation, and muscle strength. MATERIAL AND METHODS: A total of 30 male participants were divided into three groups: the incline hopping (IH) group, which performed continuous jumps on a 15° inclined surface; the plane hopping (PH) group, which performed jumps on a plane surface; and the electrostimulation (EMS) group (n = 10 for each group). All groups trained four times weekly, performing 10 sets of 10 jumps per session. The intervention period lasted four weeks. Participants' drop jumping ability was assessed before and immediately after the training period using hip, knee, and ankle kinematics and electromyographic (EMG) activity of the medial gastrocnemius (MGas), tibialis anterior (TA), rectus femoris (RF), and semitendinosus (ST) muscles. In addition, maximal isokinetic plantar flexor force measurements were evaluated in eccentric and concentric conditions. RESULTS: Analysis of variance (ANOVA) revealed that only the inclined hopping showed significant improvements in the take-off velocity (Vto) of the fast drop jump (bounce drop jump (BDJ)) (p < 0.05). These improvements were accompanied by significantly higher MGas activity during the propulsion phase of the jump (p < 0.05). In addition, all groups demonstrated greater eccentric torque (p < 0.05), while IH also improved concentric torque (p < 0.05). CONCLUSIONS: The results support the efficacy of inclined hopping in improving the Vto of BDJs. The increased MGas activity and stable co-activation index (CI) during the propulsion phase are likely to contribute to these improvements. Coaches should consider incorporating incline hopping into the periodization of athletes, while level hopping and electrostimulation could be used to increase overall strength.

Investigating Differences in Personality Traits, Self-Esteem, Eating Attitudes, and Body Image among Participants in Indoor and Outdoor Fitness Activities.

Physical activity environments influence physical condition, nutrition, individual and social behaviors, and emotional well-being. The aim of the study was to investigate differences in eating attitudes, self-esteem, personality traits, and body image among participants in indoor and outdoor leisure-time fitness programs. Participants included 1747 adults (882 men and 865 women) aged 34 ± 9.2 years, divided into experimental and control groups. All participants completed the Demographic Characteristics Questionnaire, the Eating Attitudes Test 26 (EAT-26), the Self-Esteem Scale (RSES), the Traits Personality Questionnaire 5 (TPQue5), and the Appearance Scales of the Multidimensional Body-Self Relations Questionnaire (MBSRQ-AS). The results revealed statistically significant differences between groups. One-way analysis of variance (ANOVA) revealed noteworthy variations in personality trait scores between the groups (neuroticism, extraversion, and conscientiousness) as well as body image factors (self-esteem and eating attitudes). Two-way ANOVA revealed a significant interaction between gender and participation in different types of exercise. Females had lower self-esteem and body area satisfaction scores but higher eating disorder proneness, neuroticism, appearance evaluation, and overweight preoccupation scores than males. These findings add to the current literature focusing on the psychosocial and behavioral mechanisms associated with physical activity and exercise environments. The findings provide an effective supplement to promote public health-focused fitness programs and leisure-time physical activity motivation strategies.