Intraday Analysis of Market Integration: Dutch Blue Chips traded in Amsterdam and New York

Market integration is studied for Dutch stocks cross-listed at the NYSE.Trading starts in Amsterdam and ends in New York with a one-hour overlap.Both markets are not perfectly integrated in that they can be viewed as onemarket with the well-documented U-shape in volatility, volume and spread.Increased values for the hour of overlap suggest informed trading. Zoomingin on this hour, markets are integrated in that price discovery on bothsides of the Atlantic reflects the same underlying, new information. Notconsistent across all stocks is the origin of this information, Amsterdam,New York or both

Preventing ankle sprain recurrences in sports: athletes back in balance?

Mechelen, W. van [Promotor]Verhagen, E.A.L.M. [Copromotor

Predictive Musculoskeletal Simulation Using Optimal Control: Effects of Added Limb Mass on Energy Cost and Kinematics of Walking and Running

When designing sports equipment, it is often desirable to predict how certain design parameters will affect human performance. In many instances, this requires a consideration of human musculoskeletal mechanics and adaptive neuromuscular control. Current computational methods do not represent these mechanisms, and design optimization typically requires several iterations of prototyping and human testing. This paper introduces a computational method based on musculoskeletal modeling and optimal control, which has the capability to predict the effect of mechanical equipment properties on human performance. The underlying assumption is that users will adapt their neuromuscular control according to an optimality principle, which balances task performance with a minimization of muscular effort. The method was applied to the prediction of metabolic cost and limb kinematics while running and walking with weights attached to the body. A two-dimensional musculoskeletal model was used, with nine kinematic degrees of freedom and 16 muscles. The optimal control problem was solved for two walking speeds and two running speeds, and at each speed, with 200 g and 400 g masses placed at the thigh, knee, shank and foot. The model predicted an increase in energy expenditure that was proportional to the added mass and the effect was largest for a mass placed on the foot. Specifically, the model predicted an energy cost increase of 0.74% for each 100 g mass added to the foot during running at 3.60 m/s. The model also predicted that stride length would increase by several millimetres in the same condition, relative to the model without added mass. These predictions were consistent with previously published human studies. Peak force and activation remained the same in most muscles, but increased by 26% in the hamstrings and by 17% in the rectus femoris for running at 4.27 m/s with 400 g added mass at the foot, suggesting muscle-specific training effects. This work demonstrated that a musculoskeletal model with optimal control can predict the effect of mechanical devices on human performance, and could become a useful tool for design optimization in sports engineering. The theoretical background of predictive simulation also helps explain why human athletes have specific responses when exercising in an altered mechanical environment

Effect of unsupervised home based proprioceptive training on recurrences of ankle sprain: randomised controlled trial

Objective To evaluate the effectiveness of an unsupervised proprioceptive training programme on recurrences of ankle sprain after usual care in athletes who had sustained an acute sports related injury to the lateral ankle ligament

Effect of combinations of passive and active warming on muscle temperature and sprint performance

Muscle temperature (Tm) has a significant effect on muscle function, force and power production [1], hence the adoption of warm up procedures before power based events. In the majority of sprint or power based events there are periods of maximal activity interspersed with periods of low or no activity, during which Tm may decline, adversely affecting subsequent performance. We have previously shown that Tm will decline during 30 minutes of inactivity following the completion of a warm up, and that the use of passive external heating between warm up completion and sprint cycling performance reduces Tm decline and improves peak power output [2]. The aim of the present study was to follow on from our first Tm study and determine whether, apart from using the electrical heating between warm up and event, there is an additional benefit of using the electrical heating during warm up completion on muscle temperature and subsequent measures of sprint cycling performance. The secondary goal was to look at the efficacy of a redesigned heating system covering a larger area of muscle than in [2]

Reducing muscle temperature drop post warm-up improves sprint cycling performance

PURPOSE: This study aimed to determine the effect of passive insulation versus external heating during recovery following a sprint specific warm up on thigh muscle temperature and subsequent maximal sprint performance. METHODS: On three separate occasions, 11 male cyclists (age 24.7 ± 4.2 years, height 1.82 ± 0.72m, body mass 77.9 ± 9.8 kg; mean ± S.D.) completed a standardized 15 min intermittent warm up on a cycle ergometer, followed by a 30 min passive recovery period before completing a 30 sec maximal sprint test. Muscle temperature was measured in the vastus lateralis at 1, 2 and 3 cm depth prior to and following the warm up and immediately before the sprint test. Absolute and relative peak power output was determined and blood lactate concentration was measured immediately post-exercise. During the recovery period participants wore a tracksuit top and either i) standard tracksuit pants (CONT); ii) insulated athletic pants (INS) or; iii) insulated athletic pants with integrated electric heating elements (HEAT). RESULTS: Warm up increased Tm by approximately 2.5°C at all depths, with no differences between conditions. During recovery, Tm remained elevated in HEAT compared to INS and CONT at all depths (p<0.001). Both peak and relative power output were elevated by 9.6% and 9.1% respectively in HEAT compared to CONT (both p<0.05). The increase in blood lactate concentration was greater (p<0.05) post sprint in HEAT (6.3 ± 1.8 mmol/L) but not INS (4.0 ± 1.8 mmol/L) vs. CONT (4.1 ± 1.9 mmol/L). CONCLUSION: Passive heating of the thighs between warm up completion and performance execution using pants incorporating electrically heated pads can attenuate the decline in Tm and improve sprint cycling performance

Intravenous ATP infusions can be safely administered in the home setting: a study in pre-terminal cancer patients

The aim of the study was to investigate the safety of adenosine 5′-triphosphate (ATP) administration at home in pre-terminal cancer patients. Included were patients with cancer for whom medical treatment options were restricted to supportive care, who had a life expectancy of less than 6 months, a World Health Organization performance status 1 or 2, and suffered from at least one of the following complaints: fatigue, anorexia or weight loss >5% over the previous 6 months. Side effects were registered systematically on a standard form according to the National Cancer Institute (NCI) Common Toxicity Criteria. Fifty-one patients received a total of 266 intravenous ATP infusions. Of these, 11 infusions (4%) were given at the lowest dose of 20 μg kg−1 min−1, 85 infusions (32%) at 25–40 μg kg−1 min−1, and 170 (64%) at the highest dose of 45–50 μg kg−1 min−1 ATP. The majority of ATP infusions (63%) were without side effects. Dyspnea was the most common side effect (14% of infusions), followed by chest discomfort (12%) and the urge to take a deep breath (11%). No symptoms of cardiac ischemia occurred in any of the infusions. All side effects were transient and resolved within minutes after lowering the ATP infusion rate. Side effects were most frequent in the presence of cardiac disorders. We conclude that ATP at a maximum dose of 50 μg kg−1 min−1 can be safely administered in the home setting in patients with pre-terminal cancer