Being wheelchair dependent may cause limitations in functioning, i.e. impede functions of daily l... more Being wheelchair dependent may cause limitations in functioning, i.e. impede functions of daily living (ADL) and/or participation, as is exemplified in the International Classification of Functioning, Disability and Health (ICF). To improve ambulation, the wheelchair-user combination can be optimized at three levels. On the level of the user one can optimize physical capacity and technique by training. The second level focuses on the wheelchair-user interface, i.e. the interaction between the human system and the geometry of both the seating orientation and propulsion mechanism, aiming for a higher efficiency. This is operationalized as a better ratio of internal power from the user to the external power required for propulsion. Finally, at the level of the wheelchair the focus lies on minimizing power loss of the wheelchair-user system by reducing frictional forces and optimizing the vehicle mechanics. To advance wheelchair design, better insight in the working mechanisms of our bi...
Background / Purpose: Theoretically, faster end times are expected when performing an explosive s... more Background / Purpose: Theoretically, faster end times are expected when performing an explosive start in a 1500m time trial in speed skating and cycling. In practice this appears to be particularly true in cycling, but not as much in speed skating. Main conclusion: Cyclists seem to go more all out, whereas speed skaters seem to attribute part of their energy resources to maintaining knee angles and thereby their technical ability. This might explain the different pacing strategies in speed skating and in cycling and might afford interesting possibilities to study regulation systems.
The wheelchair athlete and his/her wheelchair are inseparable and must seamlessly interface as a ... more The wheelchair athlete and his/her wheelchair are inseparable and must seamlessly interface as a complete unit. After injury or trauma resulting in some degree of lower body paralysis a shift occurs which implies a transfer from leg to arm work. Arm work is less efficient and more straining compared to leg work, and can lead to lower physical capacity. Risks of mechanical overuse are higher and because of overuse injuries, mobility can decrease. Nevertheless, high level sports performance is possible with subsequent increases in physical fitness, health and mobility. Not only wheelchair athletes, but also individuals with lower-limb loss compete at high levels in Paralympic running events with prosthetic devices. At the elite level, runners with artificial limbs/lower-limb prostheses has even been suggested to have the potential to outperform able bodied runners, which is an ongoing topic of debate. The first section of this chapter will discuss how knowledge of user interface and s...
Topsprinters in de atletiek halen snelheden van meer dan 12 m/s. Tot voor kort was dit niet wegge... more Topsprinters in de atletiek halen snelheden van meer dan 12 m/s. Tot voor kort was dit niet weggelegd voor hardlopers met een onderbeenprothese. De afgelopen jaren is de ‘Running Specific Prosthesis’(RSP) echter verder ontwikkeld. Bladerunner Oscar Pistorius verbaasde vriend en vijand door bijna net zo snel te rennen als ‘s werelds beste sprinters. Komt dit door zijn eigen lichamelijke vermogen, of is het (vooral) te danken aan dit hulpmiddel?
Cycle sport is characterised by a range of events, each varying in duration, type and the topogra... more Cycle sport is characterised by a range of events, each varying in duration, type and the topography over which the race is run. The duration of these events might last from 30 seconds for a 1 km track time trial to in excess of 100 hours over multiple days for a Grand Tour. Consequently, the physiological demands of these events are extremely different and, as a result, the approaches that need to be taken during such races differ dramatically. The aim of the cyclist racing a track time trial is to complete the distance in the fastest possible time, the winner being the quickest rider. These types of event are often characterised by pacing strategies in which the cyclist produces as fast a start as possible before then attempting to limit the fatigue-related decline in speed until they have crossed the finishing line. This pacing strategy is complicated if several cyclists compete at the same time, as in a team pursuit, where drafting comes in to play. However, not all cycling even...
Background / Purpose: The study aims to gain insight into gender differences in exercise capacity... more Background / Purpose: The study aims to gain insight into gender differences in exercise capacity during hand cycling in order to customize exercise guidelines. Main conclusion: Based on the results of the present study, there is a gender-related difference in hand cycling exercise capacity, that has to be kept in mind when prescribing training intensities for females in a rehabilitation setting.
Hoog intensieve interval training (HI-IT) is tegenwoordig een belangrijk onderdeel in trainingspr... more Hoog intensieve interval training (HI-IT) is tegenwoordig een belangrijk onderdeel in trainingsprogramma’s van duursporters. Waar in voorgaande jaren de positieve effecten van HI-IT op met name het aerobe energie systeem meermaals zijn bewezen, valt er in de fine-tuning van deze intervaltrainingen wellicht nog veel winst te behalen.
Uit de literatuur is veelvuldig gebleken dat intervaltraining bij duursporters prestatiebevordere... more Uit de literatuur is veelvuldig gebleken dat intervaltraining bij duursporters prestatiebevorderend kan werken. Het is echter nog niet geheel duidelijk wat de achterliggende mechanismen zijn die deze prestatieverbetering bij zeer getrainde duursporters kunnen bewerkstelligen. Om trainingen optimaal en op maat aan topsporters aan te kunnen bieden is het belangrijk inzicht te krijgen in onderliggende mechanismen die een rol spelen. Laursen et al. hebben in een review mogelijke oorzaken aangeduid, maar hebben hierbij de VO2-respons buiten beschouwing gelaten. In dit review zullen daarom eventuele veranderingen in de VO¬2-respons als gevolg van intervaltraining worden besproken.
Being wheelchair dependent may cause limitations in functioning, i.e. impede functions of daily l... more Being wheelchair dependent may cause limitations in functioning, i.e. impede functions of daily living (ADL) and/or participation, as is exemplified in the International Classification of Functioning, Disability and Health (ICF). To improve ambulation, the wheelchair-user combination can be optimized at three levels. On the level of the user one can optimize physical capacity and technique by training. The second level focuses on the wheelchair-user interface, i.e. the interaction between the human system and the geometry of both the seating orientation and propulsion mechanism, aiming for a higher efficiency. This is operationalized as a better ratio of internal power from the user to the external power required for propulsion. Finally, at the level of the wheelchair the focus lies on minimizing power loss of the wheelchair-user system by reducing frictional forces and optimizing the vehicle mechanics. To advance wheelchair design, better insight in the working mechanisms of our bi...
Background / Purpose: Theoretically, faster end times are expected when performing an explosive s... more Background / Purpose: Theoretically, faster end times are expected when performing an explosive start in a 1500m time trial in speed skating and cycling. In practice this appears to be particularly true in cycling, but not as much in speed skating. Main conclusion: Cyclists seem to go more all out, whereas speed skaters seem to attribute part of their energy resources to maintaining knee angles and thereby their technical ability. This might explain the different pacing strategies in speed skating and in cycling and might afford interesting possibilities to study regulation systems.
The wheelchair athlete and his/her wheelchair are inseparable and must seamlessly interface as a ... more The wheelchair athlete and his/her wheelchair are inseparable and must seamlessly interface as a complete unit. After injury or trauma resulting in some degree of lower body paralysis a shift occurs which implies a transfer from leg to arm work. Arm work is less efficient and more straining compared to leg work, and can lead to lower physical capacity. Risks of mechanical overuse are higher and because of overuse injuries, mobility can decrease. Nevertheless, high level sports performance is possible with subsequent increases in physical fitness, health and mobility. Not only wheelchair athletes, but also individuals with lower-limb loss compete at high levels in Paralympic running events with prosthetic devices. At the elite level, runners with artificial limbs/lower-limb prostheses has even been suggested to have the potential to outperform able bodied runners, which is an ongoing topic of debate. The first section of this chapter will discuss how knowledge of user interface and s...
Topsprinters in de atletiek halen snelheden van meer dan 12 m/s. Tot voor kort was dit niet wegge... more Topsprinters in de atletiek halen snelheden van meer dan 12 m/s. Tot voor kort was dit niet weggelegd voor hardlopers met een onderbeenprothese. De afgelopen jaren is de ‘Running Specific Prosthesis’(RSP) echter verder ontwikkeld. Bladerunner Oscar Pistorius verbaasde vriend en vijand door bijna net zo snel te rennen als ‘s werelds beste sprinters. Komt dit door zijn eigen lichamelijke vermogen, of is het (vooral) te danken aan dit hulpmiddel?
Cycle sport is characterised by a range of events, each varying in duration, type and the topogra... more Cycle sport is characterised by a range of events, each varying in duration, type and the topography over which the race is run. The duration of these events might last from 30 seconds for a 1 km track time trial to in excess of 100 hours over multiple days for a Grand Tour. Consequently, the physiological demands of these events are extremely different and, as a result, the approaches that need to be taken during such races differ dramatically. The aim of the cyclist racing a track time trial is to complete the distance in the fastest possible time, the winner being the quickest rider. These types of event are often characterised by pacing strategies in which the cyclist produces as fast a start as possible before then attempting to limit the fatigue-related decline in speed until they have crossed the finishing line. This pacing strategy is complicated if several cyclists compete at the same time, as in a team pursuit, where drafting comes in to play. However, not all cycling even...
Background / Purpose: The study aims to gain insight into gender differences in exercise capacity... more Background / Purpose: The study aims to gain insight into gender differences in exercise capacity during hand cycling in order to customize exercise guidelines. Main conclusion: Based on the results of the present study, there is a gender-related difference in hand cycling exercise capacity, that has to be kept in mind when prescribing training intensities for females in a rehabilitation setting.
Hoog intensieve interval training (HI-IT) is tegenwoordig een belangrijk onderdeel in trainingspr... more Hoog intensieve interval training (HI-IT) is tegenwoordig een belangrijk onderdeel in trainingsprogramma’s van duursporters. Waar in voorgaande jaren de positieve effecten van HI-IT op met name het aerobe energie systeem meermaals zijn bewezen, valt er in de fine-tuning van deze intervaltrainingen wellicht nog veel winst te behalen.
Uit de literatuur is veelvuldig gebleken dat intervaltraining bij duursporters prestatiebevordere... more Uit de literatuur is veelvuldig gebleken dat intervaltraining bij duursporters prestatiebevorderend kan werken. Het is echter nog niet geheel duidelijk wat de achterliggende mechanismen zijn die deze prestatieverbetering bij zeer getrainde duursporters kunnen bewerkstelligen. Om trainingen optimaal en op maat aan topsporters aan te kunnen bieden is het belangrijk inzicht te krijgen in onderliggende mechanismen die een rol spelen. Laursen et al. hebben in een review mogelijke oorzaken aangeduid, maar hebben hierbij de VO2-respons buiten beschouwing gelaten. In dit review zullen daarom eventuele veranderingen in de VO¬2-respons als gevolg van intervaltraining worden besproken.
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