Below you'll find a list of all posts that have been categorized as “Dr. John Mullen”
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 …
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 …
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 …
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 …
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 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 …
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 …
Providing feedback during practice and competitions is common in all sports. Despite the difficulty of providing feedback during swimming, coaches and teammates commonly provide numerous visual and auditory cues. Sensory substitution is the skill of the nervous system to receive input from one sensory system and transmit this information to another sensory system. For example, in swimming the sensory system …
It is commonly thought the more weight one lifts during resistance training, the greater increase in muscle size (hypertrophy) occurs. Unfortunately, there is minimal evidence suggesting these two conditions correlate. Moreover, the size of a muscle is not suggested to correlate with swimming success. Instead of a percent of maximum, the total volume of weight lifted is potentially a means …
1. Please introduce yourself to the readers (how you started in the profession, education, credentials, expertise, etc) I’m a Sport and Exercise Scientist and a Senior Lecturer in Sport and Exercise Physiology at the University of Portsmouth, UK. I gained both my PhD (2007) and MSc (with distinction, 2001) from Brunel University, UK, and my BSc (Hon) from Luton University …