Coming soon, from London South Bank University, a low cost portable altitude simulator called Hybreathe. A small device that can be used at rest or during exercise, Hybreathe will bring al the benefits of altitude training to anyone who wants it, and not only the elite and wealthy.
Currently a market research survey is under way and prizes can be won by lucky respondents. Please visit www.hybreathe.com for a chance to win one of several youbreathes (a vibration respiratory training device), one of several Flexi-bar vibration training devices or Code13 t-shirts and hoodies.
To participate click here:
www.hybreathe.com
Saturday, 31 January 2009
Saturday, 14 June 2008
Fitflop video at London South Bank University
The development of Fitflop at London South Bank University by Dr Dave Cook and Darren James
Monday, 3 March 2008
youbreathe on Something for the Weekend
youbreathe was developed at London South Bank University Sport and Exercise Science Research Centre
This is a clip from BBC2's Something for the Weekend, and shows Tim Lovejoy loving youbreathe
This is a clip from BBC2's Something for the Weekend, and shows Tim Lovejoy loving youbreathe
Saturday, 16 February 2008
The dangers of air travel
The general volume of air traffic has risen greatly in recent years and an important component of this is the increase in the number of long-haul flights. According to International Civil Aviation the annual number of flight passengers exceeded 1647 million in 2006 and that number is expected to rise by 4.4 per cent each year by 2015 (World Health Organization, 2007). Contemporary aircraft can cover longer distances without the need for stop-over, thus prolonging the duration of the flight. Moreover, in order to fit more passengers on the economy class flights, the airline industry tends to put additional seats in the cabin. This reduces the already insufficient legroom space even further, consequently increasing passengers’ immobility.
The altered and restricted environment in an air-craft cabin, carries possible health risks for people aboard. One such flight-related danger is the development of a deep vein thrombosis (DVT) in the lower legs, which can lead to potentially fatal conditions, particularly pulmonary embolism (PE). DVT relates to a condition caused by the formation of a blood clot (i.e. thrombus) in deep veins usually of the legs. When such blood clot breaks off it can travel through the veins back to the heart, and eventually be pumped by the heart into the lungs causing a blockage leading to the potentially fatal condition called pulmonary embolism.
Venous thromboembolism (VTE – both DVTs and PEs) after long-haul flight was first reported more than 50 years ago (1954). Since then multiple case reports and epidemiological studies provided further evidence of an association. VTE have been connected with at least 577 deaths on 42 of 120 airlines from 1977 to 1984 (25 deaths/million departures), although a proportion of such cases go unreported (Greenleaf, et al. 2004) primarily due to the fact that majority of DVT are asymptomatic and resolve spontaneously or occur days after the flight. It is crucial to acknowledge the fact that VTE is not unique to air travel but it is a complication also associated with other modes of transport, or rather any form of prolonged immobility.
It remains unclear whether the aircraft-specific factors, such as hypobaric hypoxic conditions and lower humidity, create an increased risk compared with seated immobility at ground level. There is very little evidence for the direct causative relationship between air travel and DVT in the healthy flying population. In fact the major danger is for those people who fly with multiple risk factors for DVT. For example, mutation in certain genes responsible for increased blood coagulability, history of VTE, venous insufficiency, obesity, and infectious diseases, to name a few.
Nevertheless, various preventive treatments and techniques have been proposed as countermeasures for possible flight-induced DVT. One such procedure is exercise of the lower extremities, especially the calf (soleus and gastrocnemius) muscles, in order to increase intracapillary pressure facilitating venous flow thus preventing blood from clotting (Paganin, 2003).
What is less clear is the appropriate frequency, duration and intensity of exercise in different environments and different populations. Identification of this will help to minimise risks during travel. Here at LSBU we are currently carrying out experiments that are attempting to answer these questions.
The altered and restricted environment in an air-craft cabin, carries possible health risks for people aboard. One such flight-related danger is the development of a deep vein thrombosis (DVT) in the lower legs, which can lead to potentially fatal conditions, particularly pulmonary embolism (PE). DVT relates to a condition caused by the formation of a blood clot (i.e. thrombus) in deep veins usually of the legs. When such blood clot breaks off it can travel through the veins back to the heart, and eventually be pumped by the heart into the lungs causing a blockage leading to the potentially fatal condition called pulmonary embolism.
Venous thromboembolism (VTE – both DVTs and PEs) after long-haul flight was first reported more than 50 years ago (1954). Since then multiple case reports and epidemiological studies provided further evidence of an association. VTE have been connected with at least 577 deaths on 42 of 120 airlines from 1977 to 1984 (25 deaths/million departures), although a proportion of such cases go unreported (Greenleaf, et al. 2004) primarily due to the fact that majority of DVT are asymptomatic and resolve spontaneously or occur days after the flight. It is crucial to acknowledge the fact that VTE is not unique to air travel but it is a complication also associated with other modes of transport, or rather any form of prolonged immobility.
It remains unclear whether the aircraft-specific factors, such as hypobaric hypoxic conditions and lower humidity, create an increased risk compared with seated immobility at ground level. There is very little evidence for the direct causative relationship between air travel and DVT in the healthy flying population. In fact the major danger is for those people who fly with multiple risk factors for DVT. For example, mutation in certain genes responsible for increased blood coagulability, history of VTE, venous insufficiency, obesity, and infectious diseases, to name a few.
Nevertheless, various preventive treatments and techniques have been proposed as countermeasures for possible flight-induced DVT. One such procedure is exercise of the lower extremities, especially the calf (soleus and gastrocnemius) muscles, in order to increase intracapillary pressure facilitating venous flow thus preventing blood from clotting (Paganin, 2003).
What is less clear is the appropriate frequency, duration and intensity of exercise in different environments and different populations. Identification of this will help to minimise risks during travel. Here at LSBU we are currently carrying out experiments that are attempting to answer these questions.
Friday, 15 February 2008
Step-to-step transitions are mechanically different during walking.
Step-to-step transitions are mechanically different during walking.
Darren James
Sport & Exercise Research Centre, London South Bank University.
Ever wondered how we walk? The answer for the majority of us is probably not. But it was the asking of this question that led to the development of FitFlopTM, which was designed as a training aid to increase the metabolic cost of walking.
Generally, it is not until the ability to walk is taken away such as during injury and in disease do we realise what we have lost. Our gait pattern is as unique and individual as our DNA, yet while each step appears on the surface to be repeatable this cannot be said for the internal mechanics that govern this motion.
Take for example the below illustration, which clearly shows how quadriceps (m. vasti medialis) muscle activity alters with each step during undisturbed barefoot walking. The top half of the diagram consists of the power from each step resulting from accelerations recorded at the lower leg of a 59kg female subject aged 19. Dr. Joseph Hamill and colleagues at the University of Massachusetts, USA, have previously used this method of analysis in a 1995 study. Each graph produces two distinct peaks which relate to the power resulting from active movement and a higher frequency peak associated with energy due to ground impact.
The first graph (from left to right) is the initiation step which shows low power in both peaks due to a lack of momentum. In the next step, the power of active movement is twice that of impact, and shows greater muscle activity than the initiation step. Is this too much central control? Obviously so, as the next step shows reduced active movement power but greater power of the ground impact peak suggesting a greater reliance on an eccentric contraction of the knee extensor muscle to effectively damp the resulting shock transmission. Consequently, because of this, the system is tuned for the next step (last graph – far right) with the greatest recorded active movement power and muscle activity, and reduced impact power.
So what? Well this clearly describes the energetics of walking by highlighting that the magnitude of low frequency power from ground impact is a result of alterations in muscle activity. This understanding is beneficial in the design of footwear for healthy people, clinical interventions or as training tools.
If we can show that manipulations in footwear increase lower extremity muscle activity, such as FitFlopTM; then the exercise ratio of return (ROR) may well exceed that of other fitness activities in providing an effective workout by simply wearing a form shoe.
So by safely perturbing your gait pattern it is possible to increase the metabolic cost of walking and increase the training benefits of low impact activities such as walking.
Darren James
Sport & Exercise Research Centre, London South Bank University.
Ever wondered how we walk? The answer for the majority of us is probably not. But it was the asking of this question that led to the development of FitFlopTM, which was designed as a training aid to increase the metabolic cost of walking.
Generally, it is not until the ability to walk is taken away such as during injury and in disease do we realise what we have lost. Our gait pattern is as unique and individual as our DNA, yet while each step appears on the surface to be repeatable this cannot be said for the internal mechanics that govern this motion.
Take for example the below illustration, which clearly shows how quadriceps (m. vasti medialis) muscle activity alters with each step during undisturbed barefoot walking. The top half of the diagram consists of the power from each step resulting from accelerations recorded at the lower leg of a 59kg female subject aged 19. Dr. Joseph Hamill and colleagues at the University of Massachusetts, USA, have previously used this method of analysis in a 1995 study. Each graph produces two distinct peaks which relate to the power resulting from active movement and a higher frequency peak associated with energy due to ground impact.
The first graph (from left to right) is the initiation step which shows low power in both peaks due to a lack of momentum. In the next step, the power of active movement is twice that of impact, and shows greater muscle activity than the initiation step. Is this too much central control? Obviously so, as the next step shows reduced active movement power but greater power of the ground impact peak suggesting a greater reliance on an eccentric contraction of the knee extensor muscle to effectively damp the resulting shock transmission. Consequently, because of this, the system is tuned for the next step (last graph – far right) with the greatest recorded active movement power and muscle activity, and reduced impact power.
So what? Well this clearly describes the energetics of walking by highlighting that the magnitude of low frequency power from ground impact is a result of alterations in muscle activity. This understanding is beneficial in the design of footwear for healthy people, clinical interventions or as training tools.
If we can show that manipulations in footwear increase lower extremity muscle activity, such as FitFlopTM; then the exercise ratio of return (ROR) may well exceed that of other fitness activities in providing an effective workout by simply wearing a form shoe.
So by safely perturbing your gait pattern it is possible to increase the metabolic cost of walking and increase the training benefits of low impact activities such as walking.
Thursday, 17 January 2008
Which Vibration Platform to Choose?
The fitness regime from outer space has landed! Over the last few years the popularity of vibration-training has increasingly grown with the development of branded machines such as PowerPlate ™ and Vibrogym ™. With the recent introduction of personal or ’domestic user’ models, the potential for greater training benefits such as strength and power is now being welcomed into our own homes.
From the current commercially available machines a basic vibration platform can cost as little as £100 while the so-called professional editions will set you back as much as £9000. Generally, much of the differences in cost are accountable to the brand name and design. The type of material used and the quality of construction are undoubtedly important factors for machine performance and durability, however aspects such as choice of colour and sleek design are factors that are unlikely to benefit neither your training results nor your bank balance.
When it comes to choosing a vibration platform it is useful to consider the following factors:
The operational parameters -
Apart from the type and duration of exercise performed, the intensity of vibration-training depends on the frequency of vibration (the number of oscillations per second, measured in Hertz, Hz) and the amplitude of the oscillatory wave (mm, cm). The higher these characteristics are the greater the mechanical vibration stimulus.
The frequency range of vibration platforms differ with each model. Collectively, the operating range of commercially available machines is around 15Hz to 60Hz. It is typical however, that machines only operate within a limited frequency range; some between 15-30Hz, others between 30-50Hz, and the majority at and around 35Hz ±10Hz, and at specific step increments. Commonly, the amplitude of vibration is a factor that can also be user-determined. Platform vibration amplitude ranges from around 0.5mm to 12mm (peak to peak displacement) depending on the specific machine. When buying a machine it is important to ensure it is capable of operating at the desired vibration intensities.
Most research has centred on 25- 40Hz, but the optimal frequencies for specific training are yet to be determined. While positive effects of WBV have been found at and around 30Hz, there has been little investigation into lower frequency vibration and whether these provide any benefit. Research activity from our department (Mileva et al., 2006) showed that a frequency as low at 10Hz for segmental vibration aided performance during resistance exercise. For whole-body vibration training however, to prevent hitting the resonant frequencies of internal body organs it is advisable that frequencies lower than 20Hz are avoided (Mester et al., 1999)
The platform dimensions -
Vibration platforms come in a range of sizes. Although machine dimensions are important from a convenience perspective, when choosing a machine it is important to check that the platform area is large enough for performing the type of exercise you require. Performing a deep two-leg squat on a 16 by 12inch platform (as for some low-cost machines) is an exercise feat in itself!
The type of vibration -
Most commercially available machines such as the PowerPlate ™ and Vibrogym ™ deliver vertical vibrations and as such the platform moves up and down. However, machines are available that deliver rotational vibration based on a pivot-system platform. As would be expected, there is some evidence to suggest that muscular responses to rotational vibration and vertical vibration differ (Abercromby et al., 2007) although both types of vibration have been shown to have beneficial effects for training (see for example Cochrane and Stannard, 2005 and Delecluse et al., 2003).
User operation -
Some machines come with pre-programmed training regimes with limited flexibility for the user to set their own training programme. If personalisation is required then a machine that allows the user to select parameters such as exercise and rest duration, and number of exercise sets (in addition to the intensity of vibration) should be chosen. Some machines have a limited duration of vibration exposure, so if longer bouts of continuous vibration training are required then the machine capabilities again need to be checked. The majority of vibration-training studies to date have involved less then 10-minutes of continuous vibration training, with many using protocols consisting of approximately 5 sets of 60secs with ~1min rest intervals.
Medical Device Directive certification -
There are a couple of vibration machines on the current market that have Medical CE Approval. To obtain such certification for a device a company needs to provide proof relating to:
-Safety and electrical compliance
-Risk Management and analysis
-Clear clinical Indications and claims
-Clinical proof of these indications
Although this certificate is not direct evidence for validating a machine, it is worth considering in order to know it is of sound operational function.
The Extras -
There are many extras that come along with the more costly platforms such as virtual trainer software, connections for peripheral equipment, and even platforms with inbuilt games consoles. If features such as these are not a necessity then there is very little sense in paying extra for machines that offer them.
Hopefully this short-guide to vibration platform basics has provided enough information for you to choose your machine. Whatever your needs, there is likely to be a machine out on the market that suits you. Good luck!
We have many scientists at LSBU researching the various effects of vibration-training. Be sure to check back for our latest research and insights!
Lisa Zaidell is a scientist at London South Bank University (LSBU) studying the effects of vibration training on the human body.
From the current commercially available machines a basic vibration platform can cost as little as £100 while the so-called professional editions will set you back as much as £9000. Generally, much of the differences in cost are accountable to the brand name and design. The type of material used and the quality of construction are undoubtedly important factors for machine performance and durability, however aspects such as choice of colour and sleek design are factors that are unlikely to benefit neither your training results nor your bank balance.
When it comes to choosing a vibration platform it is useful to consider the following factors:
The operational parameters -
Apart from the type and duration of exercise performed, the intensity of vibration-training depends on the frequency of vibration (the number of oscillations per second, measured in Hertz, Hz) and the amplitude of the oscillatory wave (mm, cm). The higher these characteristics are the greater the mechanical vibration stimulus.
The frequency range of vibration platforms differ with each model. Collectively, the operating range of commercially available machines is around 15Hz to 60Hz. It is typical however, that machines only operate within a limited frequency range; some between 15-30Hz, others between 30-50Hz, and the majority at and around 35Hz ±10Hz, and at specific step increments. Commonly, the amplitude of vibration is a factor that can also be user-determined. Platform vibration amplitude ranges from around 0.5mm to 12mm (peak to peak displacement) depending on the specific machine. When buying a machine it is important to ensure it is capable of operating at the desired vibration intensities.
Most research has centred on 25- 40Hz, but the optimal frequencies for specific training are yet to be determined. While positive effects of WBV have been found at and around 30Hz, there has been little investigation into lower frequency vibration and whether these provide any benefit. Research activity from our department (Mileva et al., 2006) showed that a frequency as low at 10Hz for segmental vibration aided performance during resistance exercise. For whole-body vibration training however, to prevent hitting the resonant frequencies of internal body organs it is advisable that frequencies lower than 20Hz are avoided (Mester et al., 1999)
The platform dimensions -
Vibration platforms come in a range of sizes. Although machine dimensions are important from a convenience perspective, when choosing a machine it is important to check that the platform area is large enough for performing the type of exercise you require. Performing a deep two-leg squat on a 16 by 12inch platform (as for some low-cost machines) is an exercise feat in itself!
The type of vibration -
Most commercially available machines such as the PowerPlate ™ and Vibrogym ™ deliver vertical vibrations and as such the platform moves up and down. However, machines are available that deliver rotational vibration based on a pivot-system platform. As would be expected, there is some evidence to suggest that muscular responses to rotational vibration and vertical vibration differ (Abercromby et al., 2007) although both types of vibration have been shown to have beneficial effects for training (see for example Cochrane and Stannard, 2005 and Delecluse et al., 2003).
User operation -
Some machines come with pre-programmed training regimes with limited flexibility for the user to set their own training programme. If personalisation is required then a machine that allows the user to select parameters such as exercise and rest duration, and number of exercise sets (in addition to the intensity of vibration) should be chosen. Some machines have a limited duration of vibration exposure, so if longer bouts of continuous vibration training are required then the machine capabilities again need to be checked. The majority of vibration-training studies to date have involved less then 10-minutes of continuous vibration training, with many using protocols consisting of approximately 5 sets of 60secs with ~1min rest intervals.
Medical Device Directive certification -
There are a couple of vibration machines on the current market that have Medical CE Approval. To obtain such certification for a device a company needs to provide proof relating to:
-Safety and electrical compliance
-Risk Management and analysis
-Clear clinical Indications and claims
-Clinical proof of these indications
Although this certificate is not direct evidence for validating a machine, it is worth considering in order to know it is of sound operational function.
The Extras -
There are many extras that come along with the more costly platforms such as virtual trainer software, connections for peripheral equipment, and even platforms with inbuilt games consoles. If features such as these are not a necessity then there is very little sense in paying extra for machines that offer them.
Hopefully this short-guide to vibration platform basics has provided enough information for you to choose your machine. Whatever your needs, there is likely to be a machine out on the market that suits you. Good luck!
We have many scientists at LSBU researching the various effects of vibration-training. Be sure to check back for our latest research and insights!
Lisa Zaidell is a scientist at London South Bank University (LSBU) studying the effects of vibration training on the human body.
Subscribe to:
Posts (Atom)