Sports Sciences Commons^™

Relative Importance And Plasticity Of Anatomical And Neuromuscular Factors Affecting Joint Torque Production, Joanne C. Trezise

Theses: Doctorates and Masters

The present research aimed to determine (i) the relative influence anatomical and neuromuscular variables on maximal isometric, concentric and eccentric knee extensor torque (Study 1); (ii) whether the change in strength following a 10-week strength training program is associated with changes in specific anatomical and neuromuscular variables (Study 2a); (iii) whether anatomical and neuromuscular adaptations are dependent on their pre-training magnitudes; and (iv) whether it is possible to ‘predict’ an individual’s adaptation to strength training based on their anatomical and neuromuscular pre-training magnitudes (Study 2b).

The variables assessed throughout the studies include muscle cross-sectional area (CSA), fascicle length and angle …

Muscle Damage And Metabolic Profiles Of Eccentric Cycling, Luis Penailillo

Theses: Doctorates and Masters

Eccentric cycling, in which the knee extensor muscles perform eccentric contractions while trying to brake the backward rotational movements of the cranks of a cycle ergometer, has been shown to effectively increase muscle function and volume with a low metabolic cost. However, acute responses to repeated eccentric cycling bouts have not been well documented. Thus, the primary purposes of this PhD project were to investigate muscle damage and metabolic profiles of eccentric cycling in comparison to concentric cycling (Studies 1-3), and muscle-tendon behaviour (Study 4) during eccentric cycling in relation to muscle damage.

Study 1 compared muscle damage and metabolic …

The Influence Of External Loading And Speed Of Movement On Muscle-Tendon Unit Behaviour And Its Implications For Training, Jacob Earp

Theses: Doctorates and Masters

In this thesis great emphasis has been placed on vastus lateralis (VL) muscle-tendon unit (MTU) structure, behaviour/movement and adaptation. Of particular interest was how external loading and movement speed influence these variables. In the first study (Chapter 3) we developed a new methodology by which electromyography (EMG) could be normalised during large range of motion knee extensions. This methodology was then used as part of a larger study, which investigated how external loading influenced the interaction of muscle and tendon (MTU behaviour) during stretch shortening cycle isoinertial knee extensions, and how muscle activity and intrinsic tendon force (Ft) influenced MTU …

Changes In Muscle Function And Motorneuron Excitability Of The Triceps Surae Following A Bout Of Fatiguing Eccentric Exercise, Mikala Pougnault

Theses : Honours

A reduction in capacity of the neuromuscular system associated with exercise can occur from a wide range of physiological and psychological factors. Many researchers have investigated neural activation during exercise, or the effects of muscle damage associated with eccentric exercise, but few have studied the prolonged effects of a bout of eccentric exercise on strength and motorneuron excitability. Eleven male and female subjects (aged 20-43 years) were tested to determine the effects of a fatiguing bout of eccentric exercise upon maximal isometric plantarflexion strength, motorneuron excitability, and neural activation of the soleus (SOL) and medial gastrocnemius (MG). The exercise consisted …

The Effect Of Eccentric And Concentric Training On The Size And Strength Of Human Skeletal Muscle, Haydn J. N. Mcdonald

Theses : Honours

The objective of this study was to determine if the high forces generated through eccentric contractions, and the subsequent damage sustained, contributes to greater growth and force increase in human skeletal muscle than other contraction types, and whether damage from eccentric exercise effects the increase in torque and muscle size expected after a progressive concentric strength training program. 20 healthy subjects were split into four groups which participated in 3 different training protocols, with one group serving as the control (C). Groups underwent either concentric training (CT), eccentric damage (ED), or a combination of the two protocols (DC) with the …

The Effect Of Long Term Training On The Bone Mineral Density And Muscle Strength Of Perimenopausal Athletes, Jan Dook

Theses: Doctorates and Masters

The aim of this research was to determine if long term training (20 years+) in a high impact weight bearing sport (netball/basketball: NB/88), a low impact weight-bearing sport (running/ field hockey: GEN) and a non weight-bearing sport, swimming (SWI) produced a positive relationship with regional bone mineral density (BMD) and muscle strength. Method: Three groups of perimenopausal athletes (n=20) plus a control group (CON) (n=20) had Total Body BMD and body composition measured by DEXA (Hologic QDR 2000) and isometric strength of dominant arm flexors and leg extensors by a strain tensiometer connected to a strength chair. Differences between groups …