Peter Maulder

Effectiveness of Foot Orthoses for Treatment and Prevention of Lower Limb Injuries : A Review

Healthcare professionals prescribe foot orthoses (FOs) for treatment and prevention of lower limb injuries, but previous reviews of the effectiveness of FOs have been inconclusive. We have therefore performed a review emphasizing the magnitude of treatment effects to evaluate the clinical effectiveness of FOs in the treatment and prevention of lower limb injuries.Qualifying studies were mainly controlled trials, but some uncontrolled clinical trials of patients with chronic injuries were analysed separately. Injuries included plantar fasciitis, tibial stress fractures and patellofemoral pain syndrome; these were included because of the large treatment costs for these frequent injuries in New Zealand. Outcomes were pain, comfort, function and injury status. Continuous measures were expressed as standardized differences using baseline between-subject standard deviations, and magnitudes were inferred from the intersection of 90% confidence intervals with thresholds of a modified Cohen scale. Effects based on frequencies were expressed as hazard ratios and their magnitudes were inferred from intersection of confidence intervals with a novel scale of thresholds.The effects of FOs for treatment of pain or injury prevention were mostly trivial. FOs were not effective in treating or preventing patellofemoral pain syndrome. Some studies showed moderate effects for treatment of plantar fasciitis. Only a few studies showed moderate or large beneficial effects of FOs in preventing injuries.Customized semi-rigid FOs have moderate to large beneficial effects in treating and preventing plantar fasciitis and posterior tibial stress fractures, and small to moderate effects in treating patellofemoral pain syndrome. Given the limited randomized controlled trials or clinical controlled trials available for the injuries of interest, it may be that more or less benefit can be derived from the use of FOs, but many studies did not provide enough information for the standardized effect sizes to be calculated. Further research with randomized controlled trials is needed to establish the clinical utility of a variety of FOs for the treatment and prevention of various lower limb injuries.

Biological movement variability during the sprint start: Performance enhancement or hindrance?

In the current study, we quantified biological movement variability on the start and early acceleration phase of sprinting. Ten male athletes aged 17–23 years (100-m personal best: 10.87 ± 0.36 s) performed four 10-m sprints. Two 250-Hz cameras recorded the sagittal plane action to obtain the two-dimensional kinematics of the block start and initial strides from subsequent manually digitized APAS motion analysis. Infra-red timing lights (80 Hz) were used to measure the 10-m sprinting times. The coefficient of variation (CV%) calculation was adjusted to separate biological movement variability (BCV%) from estimates of variability induced by technological error (SEM%) for each individual sprinter and measure. Pearsons product–moment correlation and linear regression analysis were used to establish relationships between measures of BCV% and 10-m sprint start performance (best 10-m time) or 10-m sprint start performance consistency (10-m time BCV%) using SPSS version 12.0. Measurement error markedly inflated traditional measures of movement variability (CV%) by up to 72%. Variability in task outcome measures was considerably lower than that observed in joint rotation velocities. Consistent generation of high horizontal velocity out of the blocks led to more stable and faster starting strides.

Are Anthropometric, Flexibility, Muscular Strength, and Endurance Variables Related To Clubhead Velocity in Low- And High-Handicap Golfers?

Keogh, JWL, Marnewick, MC, Maulder, PS, Nortje, JP, Hume, PA, and Bradshaw, EJ. Are anthropometric, flexibility and muscular strength and endurance variables related to clubhead velocity in low- and high-handicap golfers? J Strength Cond Res 23(6): 1841-1850, 2009-The present study assessed the anthropometric profile (International Society for the Advancement of Kinanthropometry protocol), flexibility, muscular strength, and endurance of 20 male golfers. These data were collected in order to determine: a) the relationship between these kinanthropometric measures and clubhead velocity; and b) if these measures could distinguish low-handicap (LHG) and high-handicap (HHG) golfers. Ten LHG (handicap of 0.3 ± 0.5) and 10 HHG (handicap of 20.3 ± 2.4) performed 10 swings for maximum velocity and accuracy with their own 5-iron golf club at a wall-mounted target. LHG hit the target significantly more (115%) and had a 12% faster clubhead velocity than HHG (p < 0.01). The LHG also had significantly (28%) greater golf swing-specific cable woodchop (GSCWC) strength (p < 0.01) and tendencies for greater (30%) bench press strength and longer (5%) upper am and total arm (4%) length and less (24%) right hip internal rotation than HHG (0.01 < p < 0.05). GSCWC strength was significantly correlated to clubhead velocity (p < 0.01), with bench press and hack squat strength as well as upper arm and total arm length also approaching significance (0.01 < p < 0.05). Golfers with high GSCWC strength and perhaps greater bench press strength and longer arms may therefore be at a competitive advantage, as these characteristics allow the production of greater clubhead velocity and resulting ball displacement. Such results have implications for golf talent identification programs and for the prescription and monitoring of golf conditioning programs. While golf conditioning programs may have many aims, specific trunk rotation exercises need to be included if increased clubhead velocity is the goal. Muscular hypertrophy development may not need to be emphasized as it could reduce golf performance by limiting range of motion and/or increasing moment of inertia.

The effect of biological movement variability on the performance of the golf swing in high- and low-handicapped players.

The purpose of this study was to examine the role of neuromotor noise on golf swing performance in high- and low-handicap players. Selected two-dimensional kinematic measures of 20 male golfers (n = 10 per high- or low-handicap group) performing 10 golf swings with a 5-iron club was obtained through video analysis. Neuromotor noise was calculated by deducting the standard error of the measurement from the coefficient of variation obtained from intra-individual analysis. Statistical methods included linear regression analysis and one-way analysis of variance using SPSS. Absolute invariance in the key technical positions (e.g., at the top of the backswing) of the golf swing appears to be a more favorable technique for skilled performance.

Kinematic alterations due to different loading schemes in early acceleration sprint performance from starting blocks

Maulder, PS, Bradshaw, EJ, and Keogh, JWL. Kinematic alterations due to different loading schemes in early acceleration sprint performance from starting blocks. J Strength Cond Res 22(6): 1992-2002, 2008-The purpose of this study was to examine the changes to block start and early acceleration sprint kinematics with resisted sled towing. Ten male sprinters performed 12 sprints (four each of unresisted and approximately 10 and 20% body mass [BM]) for 10 m from a block start. Two-dimensional high-speed video footage (250 Hz) of the starting action and the first three steps of each sprint were recorded to enable the sagittal sprinting kinematic parameters to be obtained using APAS motion analysis software. The overall results of this study indicated that early acceleration sprint performance from starting blocks decreases with increasing load during resisted sled towing. A load of approximately 10% BM had no “negative” effect on sprint start technique or step kinematic variables measured in this study (with the exception of one variable) and was also within the “no greater than 10% decrease in speed” limits suggested by Jakalski. Towing a load of approximately 20% BM increased the time spent in the starting blocks and induced a more horizontal position during the push-off (drive) phase. The approximately 20% BM load also caused the sprinters to shorten their initial strides (length), which may have resulted from the decreased flight distances. Such results suggest that the kinematic changes produced by the 10% BM load may be more beneficial than those of the 20% BM load. Future training studies will, however, need to investigate how these acute changes in sprinting technique impact on long-term adaptations in sprinting performance from resisted sprinting.

Integrating models of long-term athletic development to maximize the physical development of youth:

Long-term athletic development is important to prepare youth for sport and an active lifestyle. Several models have provided general frameworks for long-term athletic development from different perspectives that consider factors such as when to sample and specialize and what physical qualities to train and when. More recently, more specific models of long-term athletic development have emerged that focus on both specific modes of training and specific fitness qualities. This includes models focused on the development of speed, agility, power, and endurance as well as models devoted to resistance training, plyometric training, and weightlifting. These models incorporate factors such as technical competency, developmental stage, maturation, and training age to describe the long-term progression of athletic development. A challenge for the coach is to understand how these models inform one another and how they integrate into practice to allow the use of multiple modes of training to develop multiple components of fitness simultaneously throughout childhood and adolescence. This review will examine how information from various models can be integrated to maximize the physical long-term athletic development of youth.