There is variation regarding recommendations for children and adolescents carrying schoolbags. Guidelines for safe loads are mostly within 10%–15% of body weight (BW) range but include values as low as 5% and as high as 20%. Some biomechanical studies suggest that the schoolbag weight of 10% of BW may be enough to cause changes in kinematics, body posture and muscular strain. Methods of …
Foam Roll Reduces Blood Pressure After Exercise
Hypertension (HTN), characterized by increased blood pressure (BP), is quantitatively the most important risk factor for premature cardiovascular disease (CVD). Self-myofascial release (SMR) is a type of myofascial release technique which incorporates elements of massage to reduce soft tissue pain, inflammation, and delayed-onset muscle soreness (DOMS). Methods A total of 15 (M = 8, F = 7) healthy subjects between the …
50-m Free Time Trial in Morning and Evening Result in no Performance Difference in Elite Swimmers
Based on the circadian rhythms of hormone levels, gene expression, and core body temperature, it could be expected that the best performance in terms of strength, flexibility, alertness, and anaerobic power output occurs in the late afternoon. Indeed, improvements of 3.6% for 50 m, 1.9% for 100 m, and 0.8% for 400 m swimming performance were observed in the afternoon/evening …
Eight-Week Battle Rope Training Basketball Shooting Accuracy, Will it Improve Swimming Stroke Biomechanics?
Previous studies have shown that shooting accuracy is a crucial factor distinguishing between winning and losing basketball teams. Battle rope (BR) interval training is a low-impact, total-body, and intense metabolic modality. Methods Thirty male well-trained Division-I basketball players (age range: 18–25 years; basketball training: 6.7 ± 3.8 years) who had not sustained neuromuscular injury in the prior 6 months participated …
How Repeated Stretches Affect Muscle Viscoelasticity
Viscoelasticity is the ability to return of a material to return to a position after an extended force application. Dynamic tissues (muscles, tendons, ligaments) possess viscoelastic structures. The ideal mechanism and benefits of stretching are uncertain, but previous work suggests constant-torque is more beneficial than constant-angle for improving muscle creep, resulting in a decrease in stiffness. This creep is the …
Effect of Squat Depth and Load on Muscular Effort
The squat is a popular dry-land exercise for swimming. This is likely due to the numerous muscles involved and the common belief this motion mimics a flip turn (despite contradictory research). However, the effect the depth and load on the squat are unknown. Muscle force is hard to measure, therefore motion analysis techniques combined with the equations to solve for …
Variation in Body Center of Mass During Freestyle
Body position is deemed an important variable for swimming success. However, body position is typically regarded as a static position in freestyle, despite noticeable undulation during the swims of many elite middle-distance swimmers. Perhaps more importantly, external work depends on changes in the position and velocity of the center of mass (CM), which is typically expressed as the intracycle velocity variation …
Kinematics of the Thoracic Spine in Trunk Rotation
Thoracic spine rotation is used in long-axis swimming. Therefore, understanding the biomechanical demand of this motion is mandatory to understand the optimal hydrodynamics. Unfortunately, the thoracic spine is rarely researched due to the low volume of injuries at this region. Simply comparing the thoracic spine to other areas is unjust, as the thoracic spine has many differences from the rest …
Shoulder Kinematics During Scapular Plane Abduction
Shoulder impingement is the most common injury in swimming. Many factors contribute to shoulder impingement and one is inadequate space for clearance of the rotator cuff tendons during arm elevation. Previous studies have analyzed healthy shoulder range of motion with single-plane radiographs, but did not provide 3-D motion of the shoulder. Three-dimensional analyzes are necessary to understand the activity in …
Minimizing Central Motor Control Breakdown
Any repetitive task results in performance impairments over time. The cause of these decrements is typically considered physiologically induced. However, recent studies and exercise physiologist feel these impairments are influenced by the central nervous system. Transcranial magnetic stimulation (TMS) is suggested to alter the excitation of the movement areas in the brain (corticomotor tracts). The limits of maximal voluntary rate …