Maximal muscular power: lessons from sprint cycling.

Maximal muscular power production is of fundamental importance to human functional capacity and feats of performance. Here, we present a synthesis of literature pertaining to physiological systems that limit maximal muscular power during cyclic actions characteristic of locomotor behaviours, and how they adapt to training. Maximal, cyclic muscular power is known to be the main determinant of sprint cycling performance, and therefore we present this synthesis in the context of sprint cycling.

Acute changes in acceleration phase sprint biomechanics with lower body wearable resistance.

The aim of this acute cross-sectional study was to quantify the kinematic and kinetic changes that occur during sprint acceleration when lower body WR is worn. Fifteen male rugby athletes (19 years; 181 cm; 91 kg) were assessed during maximal effort over-ground and treadmill sprinting over 20 m under three different loading conditions: 0%, 3% and 5% body mass (BM) added weight attached to the lower body. Treadmill data provided a convenient estimate of kinetic changes in the absence of in-ground force plates.

Reactive and eccentric strength contribute to stiffness regulation during maximum velocity sprinting in team sport athletes and highly trained sprinters.

This study investigated the role of reactive and eccentric strength in stiffness regulation during maximum velocity sprinting (Vmax) in team sport athletes compared with highly trained sprinters. Thirteen team sport athletes and eleven highly trained sprinters were recruited. Vmax was measured using radar, and stiffness regulation was inferred from modelled vertical and leg spring stiffness.

Implementing Anaerobic Speed Reserve Testing in the Field: Validation of vVO2max Prediction From 1500-m Race Performance in Elite Middle-Distance Runners.

Purpose: Anaerobic speed reserve (ASR), defined as the speed range from velocity associated with maximal oxygen uptake (vVO2max) to maximal sprint speed, has recently been shown to be an important tool for middle-distance coaches to meet event surge demands and inform on the complexity of athlete profiles. To enable field application of ASR, the relationship between gun-to-tape 1500-m average speed (1500v) and the vVO2max for the determination of lower landmark of the ASR was assessed in elite middle-distance runners.

Methods: A total of 8 national and 4 international middle-distance runners completed a laboratory-measured vVO2max assessment within 6 wk of a nonchampionship 1500-m gun-to-tape race.

Maximal Sprint Speed and the Anaerobic Speed Reserve Domain: The Untapped Tools that Differentiate the World's Best Male 800 m Runners.

Recent evidence indicates that the modern-day men's 800 m runner requires a speed capability beyond that of previous eras. In addition, the appreciation of different athlete subgroups (400-800, 800, 800-1500 m) implies a complex interplay between the mechanical (aerial or terrestrial) and physiological characteristics that enable success in any individual runner. Historically, coach education for middle-distance running often emphasises aerobic metabolic conditioning, while it relatively lacks consideration for an important neuromuscular and mechanical component.

Anaerobic Speed Reserve: A Key Component of Elite Male 800-m Running.

Purpose: In recent years (2011-2016), men's 800-m championship running performances have required greater speed than previous eras (2000-2009). The "anaerobic speed reserve" (ASR) may be a key differentiator of this performance, but profiles of elite 800-m runners and their relationship to performance time have yet to be determined.

Methods: The ASR-determined as the difference between maximal sprint speed (MSS) and predicted maximal aerobic speed (MAS)-of 19 elite 800- and 1500-m runners was assessed using 50-m sprint and 1500-m race performance times.

Effects of Accentuated Eccentric Loading on Muscle Properties, Strength, Power, and Speed in Resistance-Trained Rugby Players.

Douglas, J, Pearson, S, Ross, A, and McGuigan, M. Effects of accentuated eccentric loading on muscle properties, strength, power, and speed in resistance-trained rugby players. J Strength Cond Res 32(10): 2750-2761, 2018-The purpose of this study was to determine the effects of slow and fast tempo resistance training incorporating accentuated eccentric loading (AEL) compared with traditional resistance training (TRT) in trained rugby players.

Reliability of horizontal force-velocity-power profiling during short sprint-running accelerations using radar technology.

Radar technology can be used to perform horizontal force-velocity-power profiling during sprint-running. The aim of this study was to determine the reliability of radar-derived profiling results from short sprint accelerations. Twenty-seven participants completed three 30 m sprints (intra-day analysis), and nine participants completed the testing session on four separate days (inter-day analysis).

Kinetic Determinants of Reactive Strength in Highly Trained Sprint Athletes.

Douglas, J, Pearson, S, Ross, A, and McGuigan, M. Kinetic determinants of reactive strength in highly trained sprint athletes. J Strength Cond Res 32(6): 1562-1570, 2018-The purpose of this study was to determine the braking and propulsive phase kinetic variables underpinning reactive strength in highly trained sprint athletes in comparison with a nonsprint-trained control group.

Tactical Behaviors in Men's 800-m Olympic and World-Championship Medalists: A Changing of the Guard.

Purpose: To assess the longitudinal evolution of tactical behaviors used to medal in men's 800-m Olympic Games (OG) or world-championship (WC) events in the recent competition era (2000-2016).

Methods: Thirteen OG and WC events were characterized for 1st- and 2nd-lap splits using available footage from YouTube. Positive pacing strategies were defined as a faster 1st lap.

Chronic Adaptations to Eccentric Training: A Systematic Review.

Background: Resistance training is an integral component of physical preparation for athletes. A growing body of evidence indicates that eccentric strength training methods induce novel stimuli for neuromuscular adaptations.

Objective: The purpose of this systematic review was to determine the effects of eccentric training in comparison to concentric-only or traditional (i.

Eccentric Exercise: Physiological Characteristics and Acute Responses.

An eccentric contraction involves the active lengthening of muscle under an external load. The molecular and neural mechanisms underpinning eccentric contractions differ from those of concentric and isometric contractions and remain less understood. A number of molecular theories have been put forth to explain the unexplained observations during eccentric contractions that deviate from the predictions of the established theories of muscle contraction.

Advances in Sprint Acceleration Profiling for Field-Based Team-Sport Athletes: Utility, Reliability, Validity and Limitations.

Background: Advanced testing technologies enable insight into the kinematic and kinetic determinants of sprint acceleration performance, which is particularly important for field-based team-sport athletes. Establishing the reliability and validity of the data, particularly from the acceleration phase, is important for determining the utility of the respective technologies.

Objective: The aim of this systematic review was to explain the utility, reliability, validity and limitations of (1) radar and laser technology, and (2) non-motorised treadmill (NMT) and torque treadmill (TT) technology for providing kinematic and kinetic measures of sprint acceleration performance.

Streptavidin: a novel immunostimulant for the selection and delivery of autologous and syngeneic tumor vaccines.

Induction of antitumor immunity using autologous tumor proteins is an attractive approach to cancer therapy. However, better methods and stimulants to present these autologous proteins back to the immune system are needed. Here, we identify streptavidin as a novel carrier protein and stimulant, and test the efficacy of both syngeneic (rat) and autologous vaccines (dogs) using streptavidin in combination with reduced soluble tumor proteins.

Insulin and fiber type in the offspring of T2DM subjects with resistance training and detraining.

Purpose: Effects of resistance training and detraining on glucose and insulin responses to an oral glucose load, muscle fiber type, and muscular performance in the offspring of those with type 2 diabetes (familial insulin resistant (FIR)) were investigated.

Methods: Six FIR participants and 10 controls (C) completed 9 wk of resistance training and 9 wk of detraining. Measures of strength and power, an oral glucose tolerance test, and a muscle biopsy to determine myosin heavy chain (MHC) fiber composition were taken at baseline (T1), after training (T2), and after detraining (T3).

Detrimental effects of west to east transmeridian flight on jump performance.

It is perceived that long haul travel, comprising of rapid movement across several time zones is detrimental to performance in elite athletes. However, available data is equivocal on the impact of long haul travel on maximal explosive movements. The aim of this study was to quantify the impact of long haul travel on lower body muscle performance.

Talent identification and deliberate programming in skeleton: ice novice to Winter Olympian in 14 months.

The aims of this study were to talent transfer, rapidly develop, and qualify an Australian female athlete in the skeleton event at the 2006 Torino Winter Olympic Games and quantify the volume of skeleton-specific training and competition that would enable this to be achieved. Initially, 26 athletes were recruited through a talent identification programme based on their 30-m sprint time. After attending a selection camp, 10 athletes were invited to undertake an intensified skeleton training programme.

Characteristics of the start in women's World Cup skeleton.

This study characterizes key elements of the start in elite female World Cup skeleton athletes. The top 20 female competitors in three World Cup races were videotaped within a calibrated space to allow the following components of the start to be quantified: (1) acceleration (velocity at 15-m mark, time to 15-m mark), (2) capacity (time to load, total number of steps to load), and (3) load (velocity at 45-m mark). A correlation analysis was used to establish the relationship between the variables of interest and overall start time (15- to 65-m mark).

Acute effect of whole-body vibration on sprint and jumping performance in elite skeleton athletes.

The winter sliding sport known as skeleton requires athletes to produce a maximal sprint followed by high speed sliding down a bobsled track. Athletes are required to complete the course twice in 1 hour and total time for the 2 runs determines overall ranking. The purpose of this investigation was to examine the effect of whole-body vibration (WBV) on lower body power to explore the utility of WBV as an ergogenic aid for skeleton competition.

Effect of long haul travel on maximal sprint performance and diurnal variations in elite skeleton athletes.

Objective: To quantify the impact of eastward long haul travel on diurnal variations in cortisol, psychological sensations and daily measurements of physical performance.

Methods: Five elite Australian skeleton athletes undertook a long haul eastward flight from Australia to Canada (LH(travel)), while seven elite Canadian skeleton athletes did not travel (NO(travel)). Salivary cortisol was measured on awakening, 60 min and 120 min after awakening.

The reliability of ten-meter sprint time using different starting techniques.

Acceleration is an important factor for success in team-sport athletes. The purpose of this investigation was to compare the reliability of 10-m sprint times when using different starting techniques. Junior male rugby players (n = 15) were tested for speed over 10 m on 2 different testing sessions.