Gerrit Jan van Ingen Schenau's research while affiliated with Vrije Universiteit Amsterdam and other places
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Publications (127)
IntroductionModelling of Speed SkatingFactors that Influence PerformanceConclusions
References
Personal and world records in speed skating improved tremendously after the introduction of the klapskate, which allows the foot to plantar flex at the end of the push-off while the full blade continues to glide on the ice. The purpose of this study was to gain insight into the differences in skating technique with conventional versus klapskates an...
In order to explain the task‐dependent activation of muscles, we have investigated the hypothesis that mono‐ and bi‐articular muscles have a different functional role in the control of multijoint movements. According to this hypothesis, bi‐articular muscles are activated in a way to control the direction of external force. The mono‐articular muscle...
The aim of this study was to examine the effect of loss of sensation in the plantar surface of the feet on the learning of a contact control task. It has previously been shown that the biarticular thigh muscles control the external force exerted by the feet by finely regulating the net knee and hip moments. Based on literature which demonstrates st...
This target article addresses the role of storage and reutilization of elastic energy in stretch-shortening cycles. It is argued that for discrete movements such as the vertical jump, elastic energy does not explain the work enhancement due to the prestretch. This enhancement seems to occur because the prestretch allows muscles to develop a high le...
From previous inverse dynamic analyses of human leg extensions, it was hypothesized that the underlying processes for the activation of mono- and biarticular muscles are different; the mono-articular muscles being activated when they shortened, whereas the biarticular muscles appeared responsible for the control of the external force direction. In...
In guided leg movements (e.g., in cycling or wheelchair propulsion), the kinematics of a limb are determined by the object on which a force is applied. As a consequence, the force direction can vary and may deviate from the movement direction, that is, the effective direction. In the present study, the relation of effective force application and ma...
Sport scientists have identified many factors as prerequisites for a good athletic performance in various sports. It is not clear whether these factors also influence the best performers in the homogeneous groups of top athletes selected for national teams. In this study, this issue is addressed with members of the Dutch National Junior Speed Skati...
The main result of this study is that biarticular leg muscles contribute significantly to the work done at joints, due to transfer of power during explosive leg extensions. In particular, a net power transfer was shown from hip to knee joint during jumping and sprinting. Seven elite athletes performed explosive one legged jump and spring push offs....
To prevent the tip of the blade from scratching through the ice, the technique in speed skating requires that plantar flexion is largely suppressed during the gliding push off. This not only prevents the plantar flexors from contributing to external work but also causes the skater to lose contact with the ice long before the knee is fully extended....
In guided movements, limb kinematics is determined by the object on which a force is applied (as in cycling). Consequently, the force direction may deviate from the effective direction. It is examined how effective force application is related to maximal power output. A recent study, where subjects performed guided leg tasks on a special dynamomete...
The purpose of this study was to describe the push-off kinematics in speed skating using three-dimensional coordinates of elite male sprinters during the first part of a speed skating sprint. The velocity of the mass center of the skater's body VC, is decomposed into an "extension" velocity component VE, which is associated with the shortening and...
The role of lower leg muscles is investigated during contact control tasks, in which the external force, applied by the foot on the surface, has to be controlled. Force, position and muscle activation were recorded. All subjects showed a stereotyped activation pattern to accomplish the tasks. The torques about hip and knee changed by a reciprocal a...
This paper addresses the question what level of detail is required in internal representations used in control of multi-joint movements, focusing on contact control tasks. Following Bernstein, we define the central problem to be which strategies are used in the nervous system in order to control the vastly redundant musculoskeletal system. Simplifi...
From an analysis of cycling, it was hypothesized that mono- and bi-articular muscles may have different roles in the control of contact control tasks. The aim of the present study is to find experimental evidence for this hypothesis. On a special dynamometer, subjects were instructed to exert a force in a prescribed direction while the forceplate w...
1. Movements often require control of direction and a magnitude of force exerted externally on the environment. Bi-articular upper leg muscles appear to play a unique role in the regulation of the net torques about the hip and knee joints, necessary for the control of this external force. 2. The aim of this study was to test the hypothesis that the...
A longitudinal analysis of a group of speed skaters was done to identify the performance-determining factors for a successful speed skating career. This paper presents both the physiological and anthropometric results of this longitudinal study. Twenty-four athletes from the Dutch National Junior Speed Skating Team were followed from age 16-17 yr t...
In contemporary textbooks on functional anatomy, the actions of muscles which cross more than one joint are often described according to the degrees of freedom which they might influence about the joints crossed. Such actions, however, might in principle also be performed by sets of mono-articular muscles crossing the same joints. In the past centu...
Most purposive movements are multi-joint actions in which specific patterns of joint moments are necessary to achieve the required segmental accelerations and to exert the appropriate direction and magnitude of force on the environment. Both human and animal studies suggest that mono- and biarticular muscles have different roles in these complex mo...
1. Humans can execute explosive movements such as jumping and hitting an object irrespective of the starting position from which these movements have to be initiated; in fact, variability of kinematic parameters has been shown to decrease in the course of the movement. 2. We address the question of whether it is necessary to adapt the stimulation p...
Sprinting performances rely strongly on a fast acceleration at the start of a sprint and on the capacity to maintain a high velocity in the phase following the start. Simulations based on a model developed in which the generation of metabolic power is related to the mechanical destinations of power showed that for short-lasting sprinting events, th...
In this study the function of leg muscles during stretch-shortening cycles in fast running (6 m.s-1) was investigated. For a single stance phase, kinematics, ground reaction forces, and EMG were recorded. First, rough estimates of muscle force, obtained by shifting the EMG curves +90 ms, were correlated with origin-to-insertion velocity (VOI). Seco...
In the hindlimb of quadrupeds three major segments can be distinguished which can rotate with respect to each other in the hip, knee and ankle joints. Movements in a sagittal plane appear to be controlled by three sets of antagonistic mono-articular muscle groups (one set per joint) and two sets of antagonistic bi-articular muscles. This design all...
Hypotheses concerning the influence of changes in the design of the human musculoskeletal system on performance cannot be tested experimentally. Computer modelling and simulation provide a research methodology that does allow manipulation of the system's design. In the present study this methodology was used to test a recently formulated hypothesis...
1. We investigated the hypothesis that mono- and bi-articular muscles perform different functions: the former are chiefly dependent on their mechanical advantage, while the latter are considered to be mainly concerned with controlling the direction of an external force. 2. Seven subjects were asked to exert a constant external force in various dire...
Direct dynamics computer simulation is gaining importance as a research tool in the biomechanical study of complex human movements. Therefore, the need for general-purpose software packages with which the equations of motion can be derived automatically and solved numerically is growing. In this paper such a method is described: SPACAR. The method...
The efficiency of a manipulator with actuators in each single
joint can be improved considerably (up to a factor of 2) by adding
actuators that act over more than a single joint. Even though this
creates redundancy the efficient control of force and position of the
manipulator end point induces a constraint that eliminates (part of) the
redundancy....
This study was designed to investigate the patterns of intermuscular coordination during a sprinting event. In previous research it was found that despite the indeterminacy problem of movement control, movements like vertical jumping, speed skating and cycling are performed in a stereotyped manner. It was hypothesized that this might be due to cons...
In sprinting events of short duration, performance depends not only on the mean external power output and the frictional losses but also on the distribution of energy over the race. To investigate the optimal distribution of anaerobic energy during cycling the 1000 m time trial and the 4000 m pursuit, we simulated a power equation which contains ex...
An analysis of the start of the 500 m speed skating races during the 1988 Olympic Winter Games showed a remarkably high correlation between the acceleration of the skater in the first second of the sprint and the final time (r = -0.75). In this study a power equation is used to explain this high coefficient of correlation. The performance in speed...
During speed skating, the external power output delivered by the athlete is predominantly used to overcome the air and ice frictional forces. Special skates were developed and used to measure the ice frictional forces during actual speed skating. The mean coefficients of friction for the straights and curves were, respectively, 0.0046 and 0.0059. T...
In many arm or leg movements the hand or foot has to exert an external force on the environment. Based on an inverse dynamical analysis of cycling, it is shown that the distribution of net moments in the joints needed to control the direction of the external force is often opposite to the direction of joint displacements associated with this task....
Seven female and eight male elite junior skaters performed cycle ergometer tests at four different times during the 1987/1988 season. The tests consisted of a Wingate-type 30-s sprint test and a 2.5-min supramaximal test. The subjects were tested in February, May and September 1987 and in January 1988. Maximal oxygen consumption was measured during...
The purpose of this study was to investigate the magnitude of electromechanical delay (EMD) and its possible dependence on muscle type, type of contraction, fatigue, level of force, initial muscle length, and muscle contraction velocity. This was achieved using an experiment that measured voluntary knee extensor torques and surface EMG activity for...
The purpose of this study was to describe the intermuscular coordination and power production for the constrained asymmetrical movement during skating the curves. Seven elite male speed skaters took part in the experiments. The speed skaters were simultaneously filmed from frontal and sagittal views. EMGs were obtained telemetrically and push-off f...
A major criticism of present models of the energetics and mechanics of sprint running concerns the application of estimates of parameters which seem to be adapted from measurements of running during actual competitions. This study presents a model which does not perpetuate this solecism. Using data obtained during supra-maximal cycle ergometer test...
Five speed skaters of elite performance level and six speed skaters of trained level were subjected to an inverse dynamical analysis during speed skating. Push-off forces were registered by means of special skates. Myoelectric activity (EMG) of ten leg muscles and cinematographic data were recorded. Linked segment modelling yielded net joint moment...
Forty‐five female handball players were trained during 8 weeks with a frequency of two sessions per week. They were divided at random into three groups of 15 subjects each: (1) a control group with normal training, using normal handballs (approximately 400 g); (2) the heavy training group (HT) exercised with a heavy ball (approximately 500 g); and...
Using kinetics of aerobic and anaerobic power production as measured during supramaximal bicycle tests of five speed skaters of international level, a model of the kinetics of power production during skating is obtained. Velocity time courses of a generalized speed skater were calculated for all Olympic distances (500 m, 1000 m, 1500 m, 5000 m, and...
The purpose of this study was to compare for a group of ten subjects the mechanical output about the ankle during isokinetic plantar flexion with that during one-legged vertical jumps. For evaluation of the mechanical output the plantar flexion moment of force was related to the angular velocity of plantar flexion. The relationship for isokinetic p...
Work output of rat gastrocnemius medialis (GM) muscle (N = 5) was measured for stretch-shortening contractions, in which initiation of stretch occurred prior to the onset of activation, and for contractions with an isometric prephase. Duration of the active prephase (prestretch and pre-isometric) varied from 20 to 200 ms. Subsequent shortening (fro...
This paper attempts to clarify the formulation of power equations applicable to a variety of endurance activities. An accurate accounting of the relationship between the metabolic power input and the mechanical power output is still elusive, due to such issues as storage and recovery of strain energy and the differing energy costs of concentric and...
Based on a model consisting of three rigid links, an instantaneous power equation has been deduced for ergometer cycling which shows a causal relationship between power liberated in joint rotation on the one hand and the rate of change of segmental energy plus the power transferred to the pedal on the other. The shape and magnitude of these two typ...
In isokinetic experiments on human subjects, conducted to determine moments that can be exerted about a joint at different angular velocities, joint rotation starts as soon as the moment increases above the resting level. This contraction history differs from the one in experiments on isolated muscle, where the force is allowed to increase to an is...
Electromechanical delay (EMD) values were obtained using a cross-correlation technique for a series of 14 repetitive submaximal dynamic isometric contractions of the vastus lateralis performed by five subjects. To avoid a phase lag, which is introduced with one-way filtering, the EMG was processed with a bi-directional application of a second-order...
Electromechanical delay (EMD) values were obtained using a cross-correlation technique for a series of 14 repetitive submaximal dynamic isometric contractions of the vastus lateralis performed by five subjects. To avoid a phase lag, which is introduced with one-way filtering, the EMG was processed with a bi-directional application of a second-order...
In textbooks on the anatomy of the musculo-skeletal system, both muscles crossing only one joint (mono-articular muscles) and muscles crossing more than one joint (multi-articular muscles) are classified according to the location of their line of action relative to joint axes of rotation (e.g. Williams and Warwick, 1980). For instance, the line of...
Simulations of a simplified form of vertical jumping were performed using a model of the lower extremity to gain insight into the relation between timing and jumping performance. The model consists of foot, lower leg and upper leg. The mass of the upper body is concentrated at the hip. The hip is allowed to move in vertical direction only, thus eli...
This study is focussed on the kinetics of the first four steps in the speed skating start. In the first four steps of the speed skating start the male and female speed skaters produce a mean power of 1240 W and 744 W respectively. For work per stroke 402 J (males) and 296 J (females) was found. Peak values of power output reached values up to 4500...
Human joints, predominantly, allow rotations to occur. As a consequence, translations of the body centre of gravity or translations of a distal segment relative to the trunk are the result of transformations of rotations in joints into the desired translations. This leads to a number of constraints associated with these transformations which depend...
Replies to the comments on the author's original article (see record
1992-29977-001) and clarifies some of the main points. The target article was meant to illustrate constraints associated with the transformation of rotations in joints as identified in inverse dynamical analyses of jumping, cycling, and skating. A 2nd aim was to show that the coo...
Mechanical characteristics of the sprint start in speed skating were measured during the 1988 Winter Olympic Games. From three-dimensional film analysis of the first 4 seconds of the male and female 500-m races, biomechanical variables were determined. The first strokes during the start appeared to be performed by a running-like technique. At a for...
The efficiency of positive work was measured for rat medial gastrocnemius muscle at 25°C during repeated contractions. Six muscles were stimulated to perform concentric contractions preceded by an active prestretch (PS contractions) and six muscles made to give concentric contractions from an isometric state (PI contractions). Both lengthening and...
In various multi-joint movements where an animal is in contact with his environment, the interaction with the environment may constrain the control of joint moments and joint displacements. If the hand or foot has to exert an external force on the ground or on an object, the joint moments necessary to control the direction of this force are to be j...
In this study the propelling efficiency (ep) of front-crawl swimming, by use of the arms only, was calculated in four subjects. This is the ratio of the power used to overcome drag (Pd) to the total mechanical power (Po) produced including power wasted in changing the kinetic energy of masses of water (Pk). By the use of an extended version of the...
Effects of different hand rim diameters in wheelchair racing were studied with respect to physiological and technique parameters at five speed levels (N = 8 wheelchair sportsmen). In each of five subsequent 15-min exercise tests on a treadmill, a different sized hand rim was mounted to the rear wheels (0.3, 0.35, 0.38, 0.47, 0.56 m). In each test,...
Eight wheelchair sportsmen conducted eight wheelchair exercise tests on a treadmill. Two workload strategies were followed: strategy 1--increments in speed at a constant slope and strategy 2--increments in slope at constant velocity. Thus, data on cardio-respiratory and propulsion technique parameters were obtained on two identical series of 16 spe...
The centripetal force in speed skating the curves has to be delivered by the push off force which also does the external work to maintain the speed. Based on the geometry of the speed skating oval and the sideward push off characteristics in speed skating, a mathematical model of the power output in skating the curves was deduced. The power require...
Force-velocity and force-length relations were obtained for the edl of four Wistar rats in order to characterise the contractile properties (CE) of these muscle-tendon complexes. Compliances of the undamped part of the series components (SE) were measured in quick length decreases. Force-extension relations of SEs were obtained by integration of co...
Six male and six female elite speed skaters were tested during two bicycle ergometer tests: a 30 s sprint test and a 2.5 min supra maximal test. During the 2.5 min test oxygen consumption was measured every 30 s. The males showed 30-31% higher mean power output values both during the sprint test (1103 versus 769 Watt) and during the 2.5 min test (5...
Propulsive arm forces of 32 male and 9 female swimmers were measured during front crawl swimming using arms only, in a velocity range between 1.0 m s-1 and 1.8 m s-1. At constant velocity, the measured mean propulsive force Fp equals the mean active drag force (Fd). It was found that Fd is related to the swimming velocity v raised to the power 2.12...
The present study was designed to investigate for vertical jumping the relationships between muscle actions, movement pattern and jumping achievement. Ten skilled jumpers performed jumps with preparatory countermovement. Ground reaction forces and cinematographic data were recorded. In addition, myoelectric activity (EMG) was recorded from seven le...
In competition cycling success usually goes to the rider most resourceful mentally and physically. Nevertheless, essentially subjective qualities can be usefully reinforced by an understanding of the various physical factors involved. These include rolling and air friction, the physiology of muscle, the weight of the machine, body posture, and air...
Actions of muscles that pass over more than one joint are mainly described with respect to movements in the joints that are crossed. In a previous study of push-off without plantar flexion it was shown that the transformation of knee angular velocity into translation of the body is constrained by the fact that velocity difference between hip and an...
Two well-trained speed-skaters were subjected to a biomechanical analysis incorporating push-off forces, cinematographic data, and link segment modeling. To gain knowledge on the backgrounds on technique and performance in speed-skating, the muscle coordination was studied by EMG and muscle contraction velocities. In speed-skating during the push-o...
In this study the mechanical output (e.g., force, contraction velocity, instantaneous power) about the ankle was measured during a jump with and without occurrence of transportation of power and pre-stretch potentiation. To examine this, a model of the m. triceps surae was used. Eleven subjects performed a maximal one-legged countermovement jump (C...
The mechanics of speed skating, as many other endurance sports, can be described by an energy flow equation. With such an equation the influence of suit, local pressure, altitude, shielding, and body position on speed is predicted. Next to these model predictions, the peculiar properties of the skating technique are discussed and their practical im...
Fourteen well-trained speed skaters performed all-out exercise tests during ice speed skating, low walking (walking-like movement in skating position), and dry skating (side to side deep sitting push-offs). These dry land training activities, widely used by speed skaters during the summer period, are compared to speed skating in relation to the con...
The dynamic passive response of the left gastrocnemius medialis muscle of thirty male Wistar rats was studied as a function of muscle dimensions and absolute and relative amount of connective tissue. Values of the absolute active and passive length-force curves (active force, passive force, active working range) correlated well (coefficients of cor...
In the literature, drop jumping is advocated as an effective exercise for athletes who prepare themselves for explosive activities. When executing drop jumps, different jumping techniques can be used. In this study, the influence of jumping technique on the biomechanics of jumping is investigated. Ten subjects executed drop jumps from a height of 2...
In the literature, athletes preparing for explosive activities are recommended to include drop jumping in their training programs. For the execution of drop jumps, different techniques and different dropping heights can be used. This study was designed to investigate for the performance of bounce drop jumps the influence of dropping height on the b...
In speed skating, performance is related to the product of the amount of work per stroke and the stroke frequency. Work per stroke is dependent on the component of the push-off force in the direction perpendicular to the gliding direction of the skate. The push-off force at different velocities was measured in three trained speed skaters. The resul...
Eight well-trained speed skaters performed three all-out tests during ice speed skating, board skating and cycling. Compared to speed skating, cycling produced significantly higher values of oxygen consumption (57.2 +/- 4.9 vs. 53.9 +/- 4.2 ml/(kg X min], ventilation (111.3 +/- 10.2 vs. 98.8 +/- 7.3 l/min) and respiratory exchange ratio (1.18 +/- 0...
Changes of circumferential dimensions and passive resistance of the human knee caused by immobilization, were studied during remobilization. Patients immobilized with a long leg cast after tibial fractures or ligamentous injuries were studied immediately after removal of the cast and after mean periods of 18, 36 and 81 days of remobilization. Immob...
Eight well trained marathon skaters performed all-out exercise tests during speed skating on ice and roller skating. To compare these skating activities in relation to the concept of training specificity, relevant physiological (V
O2,V
E, RER and heart rate) and biomechanical variables (derived from film and video analysis) were measured. There wer...
Speed skating exercise can be better understood by taking account of physiological and biomechanical considerations. Comparison with other sports shows the unique and peculiar way of skating propulsion. The relatively long lasting isometric muscle contractions during the gliding phase, alternated with high power output push-offs, place unusual dema...
Characteristics of stroke mechanics of elite and trained speed skaters were measured during the skating of curves. Film and video analysis from the 5000-meter races at the Dutch National Championships yielded biomechanical variables that were correlated to performance. There are fundamental differences in push-off mechanics between skating the stra...
Propulsive arm forces of twelve elite male swimmers during a front crawl swimming-like activity were measured. The swimmers pushed off against grips which are attached to a 23 m tube at 0.8 m under the water surface. The tube was fixed to a force transducer. Since at constant speed, mean propulsive force equals mean drag force this method also prov...
Two hand rim propelled wheelchairs, a daily-use (active) wheelchair (R) and a marathon sports wheelchair (S), were compared to a three-wheeled crank (C) and a (synchronic) lever (L) propelled wheelchair. All wheelchairs were analysed with respect to cardio-respiratory parameters ([Vdot]E, [Vdot]O2, HR, RER), power output and gross mechanical effici...
In explosive movements involving the lower extremity elastic recoil and transportation of power from knee to ankle via m. gastrocnemius allow power output about the ankle to reach values over and above the maximum power output of the plantar flexors. The object of this study was to estimate the relative power and work contributions of these two mec...
Citations
... The present study found a similar trend in the hand force's HFD under both arm-pull conditions. Propulsive force is a strong predictor of swimming velocity, and being the upper limbs the main contributors to velocity (Deschodt et al., 1999;Hollander, 1988), this link between the nonlinear properties of the swim velocity and hand force was somewhat expected. ...
![[object Object]](https://i1.rgstatic.net/ii/profile.image/272565100871689-1441995992245_Q64/Peter-Hollander-3.jpg)
... Therefore, the key factor affecting speed is the amount of work done by the athlete in each stroke [28], making it crucial for the athlete to perform work e ciently. While most sports require athletes to push forward using an opposite direction, in speed skating, athletes need to push sideways to generate forward propulsion due to the unique characteristics of ice friction [29][30]. Therefore, the performance of speed skaters largely depends on their ability to generate muscle power, and athletes must use proper movements and techniques to deliver maximum force to their skating motion. ...
![[object Object]](https://i1.rgstatic.net/ii/profile.image/928679127441411-1598425766639_Q64/Jos-De-Koning.jpg)
... Many scholars at home and abroad have conducted studies on adolescents' participation in ice sports, taking the family, school and social levels as the entry point for research, and have studied the value and influencing factors of adolescent participation in ice sports from the perspective of physical exercise [11][12][13][14][15][16][17][18][19], but fewer scholars have studied adolescents' participation in ice sports from the behaviorist level of cognitive psychology [20,21]. The willingness of adolescents to participate in ice sports is a subjective assessment of the likelihood of their future participation in ice sports, and the predictive effect of willingness to participate on sporting behavior has been validated by many studies [22]. ...
... Hesford et al. 32 also observed this phenomenon when exploring oxygenation of leg muscles, during cornering on the track. De Boer et al. 33 . they noticed, that comparing the skating on a straight line and on corners, there were much larger changes in joint movement in the right lower limb. ...
![[object Object]](https://i1.rgstatic.net/ii/profile.image/272593164959749-1442002683160_Q64/Gertjan-Ettema.jpg)
... Long track speed skaters skate with only left turns using a leftward leaning body position to resist centrifugal forces. Both limbs are used for propulsion, but the right limb push is characterized by longer ice contact times and more sustained contractions to support the mass of the athlete and resist external forces [17]. This contributes to higher intramuscular forces, increased blood flow occlusion, and asymmetrical muscle oxygenation (right > left) throughout the race [18,19]. ...
... Pendergast et al. investigated effects of geometry, mass, density and roughness factor on the speed and efficiency of economic analysis examined as the use of swim fins [4,5]. ...
... Thus, the proposed calibration scheme is only valid for the load conditions for which the calibration coefficients were calculated. Differences between ID-and sEMG-based forces may be due to the electromechanical delay [37][38][39]and to the simplification of the muscular model. Nevertheless, the proposed method could be useful in clinical applications. ...
![[object Object]](https://i1.rgstatic.net/ii/profile.image/560247362289665-1510584788828_Q64/Margriet-Mullender.jpg)
... Since the friction between the skate blade and the ice is very low [3], athletes have to use the gliding technique to generate propulsion [4,5]. This means that push-off forces against the ice must be generated in the direction perpendicular to the gliding direction of the skate [6]. ...
... Previous studies have suggested that muscles which span multiple joints have distinct functions: uni-articular muscles primarily generate force and power generators, whereas bi-articular muscles modulate the moments and powers developed about the joints they span (G. J. van Ingen Schenau et al. 1990;G. J. van Ingen Schenau et al. 1992). ...
... As the majority of children's VPA and VHPA is accumulated via short intermittent bouts rather than long continuous bouts, intermittent activity seems to be efficient to promote healthy body composition and health-related fitness. However, there is an urgent need for more longitudinal studies on children in which PA, physical fitness (or performance), and health are measured repeatedly in the same individual over an extended period of time [36,37]. ...