Galileo (vibration training)

Galileo (in the US also available as Vibraflex) is a brand of vibration training platforms used as exercise equipment as well as for therapeutic use. It consists of a vibration platform which vibrates sinusoidal side alternating like a see-saw. Depending on the device size it oscillates with an amplitude of up to 6 mm (equivalent to a peak to peak distance of 12 mm) and a frequency of 5 Hz to 30 Hz (5 to 30 repetitions per second). Due to its high amplitudes and vibration frequencies above 12 Hz it is able to utilize stretch reflexes. Galileo is manufactured in Germany by the German company Novotec Medical GmbH. Since 2004 Galileo is also available as a medical device.

Basic Function
The base plate of Galileo vibration training devices is moving like a see-saw. This side alternating motion is supposed to mimic human gait in order to utilize nearly physiological motion patterns close to the side alternating human gait. The side alternation causes the hip to tilt which requires the contra lateral muscles of the back to be activated – while one leg is lifted the other drops. Compared to vertically vibrating devices the side alternating motion results in very low acceleration acting on the centre of gravity of the upper body and the head.

Fields of Application
Side alternating vibration training is used in a wide range of applications like fitness, professional sports, prevention as well as in medical and therapeutic use.

History of Galileo Training Devices
The first Galileo patent was filed in 1996 in the same year the first Galileo device was commercially available. The first publications the new field of whole body vibration (WBV) training in 1998 used Galileo devices. Therefore the Galileo systems were the first available devices in the field of Whole Body Vibration training. While other devices like the biomechanical stimulation systems associated with the name of Vladimir Nazarov were concentrating on selected muscle groups, WBV devices allow a more systematic training since the user stands on the device. Side alternating vibration training is able to stimulate the leg muscles as well as the back in a close to physiological way quite similar to the human gait.

Also in 1996 the first Galileo vibrating dumbbell patent was filed. It was optimized for the usage at the upper body. First research on this system was published in 1999.

Since 2006 Galileo is also available as an approved medical device in Europe.

Training Parameters
The more than 180 international peer reviewed studies about whole body vibration training show quite a variance in training results even in studies which seem to be comparable on first sight. This is partly due to device specific differences (e.g. side alternation vs. vertical vibration, large differences in training amplitudes and used frequencies   ) which makes the results of studies difficult to compare. In addition many study designs seem not to incorporate the basic rules of adaptation of the training intensity to the individual as described in modern training methodology. Further more the precise training parameters are mostly described only incompletely. As a result it can often not be distinguished weather a negative outcome is related to vibration training itself or mainly to a lack of adaptation of the training to the abilities of the trainee.

The main parameters which can be altered in vibration training are:

Amplitude
The higher the amplitude the more intense the training). A higher amplitude results in a higher elongation of ligaments and muscles as well as in a higher elongation speed. Hence the amplitude influences the maximum stretching as well as the maximum motion velocity. Since the Galileo devices are based on a see-saw motion the amplitude can be varied by the foot position: the further apart the feet the larger the amplitude. If the amplitude can not be increased, additional weights (e.g. weight vests or dumbbells) can be used to increase the training stimulus.

In literature as well as in advertisements be aware that when comparing published results or devices, the amplitude (maximum displacement from equilibrium) is often confused with the peak to peak distance (displacement from the lowest to the highest point, or twice the amplitude).

Frequency
(Number of repetitions per second): by choosing a certain range of frequencies the training objective is selected. According to muscle physiology and the transmission speed of the Nerve there are at least three frequency ranges to be discriminated (the following ranges can alter slightly between individuals depending on their age, degree of fitness and genetic preposition):
 * below about 12 Hz: The round-loop time of the sensory nerves (afferent signal), its computation and the motor nerves (efferent signal) lies usually between 80 ms and 100 ms which is equivalent of a frequency of 10 Hz to 12.5 Hz. For vibration frequencies below this threshold the postural system (balance sense) is able to compensate actively each individual movement of the platform. Within this frequency range hence training is focused on Proprioception, balance but also mobilization.
 * between about 12 Hz and 20 Hz: above the roundup time there is not enough time for the body to actively respond to each individual movement of the platform. Hence it needs to use other means of reaction like the stretch reflex. The Muscle contraction time of typical muscle composition of fast and slow twitch fibres needs about 25ms, the typical relaxation time is about the same. Hence a complete cycle of contraction an relaxations needs about 50 ms which is equivalent to a frequency of 20 Hz. Below this frequency of 20 Hz all muscles in the muscle chain needed for the performed motion (with Galileo the simulated human gait) can undergo a complete contraction and relaxation cycle. Hence this range of frequencies focuses on inter and intra muscular coordination, stretching and relaxation (for examples for muscles of the lower and upper back
 * above about 20 Hz: Above a frequency of about 20 Hz there is less and less time for the muscles to relax. Hence in this frequency range with increasing frequencies the muscle tone / co contraction increases. This frequency range targets training of muscle power and muscle mass of the fast twitch fibres. For average people an increase above 30 Hz especially using the large amplitudes that can be used with Galileo results in an overburden. Only in few specialized athletes (e.g. sprinters or jumpers) training frequencies of 35 Hz or even 40 Hz can be beneficial. Good examples of this training scheme is the increased jumping height in volleyball players or the increased muscle power in elderly women.

Position & Posture
Especially in frequency ranges where stretch reflexes are triggered the position and posture standing on the device is of importance. Stretch reflexes are triggered in any tensed muscle which is additionally stretched fast enough (e.g. by vibrations). Depending on the position and posture different muscle groups are tensed. For example: standing with slightly bent knees on the fore foot focuses the training on the calf muscle, putting more weight in the same position on the heels focuses the training on the upper legs. Straitening the knees further focuses the training on the muscles of the lower back.

Repetitions
Like in any training the number of repetitions and number of training days per week are an important factor to increase efficiency. Most research on Galileo tried to optimize training effects in a minimum of time. Hence typically two training sessions per week of less than 15 minutes duration have been reported. A few reported even daily usage but for very intense training at high frequencies in order to build up muscle power and volume a rest period of at least one day as with any intense training seems to be advisable.

Research Articles on Galileo Vibration Training
With more than 100 peer reviewed publications most of them listed in PubMed starting with the work of Bosco in 1998

The fields of research done with Galileo devices include:
 * research of the basic effects


 * hormonal effects


 * stretch reflex


 * stretching


 * cardio vascular effects


 * geriatric applications (osteoporosis prevention, balance training, muscle power improvement, fall prevention)


 * therapy of incontinence


 * therapy of neurological diseases (Parkinson, Multiple Sclerosis (MS), stroke, chronic fatigue syndrome)


 * other diseases


 * therapy of back pain


 * pediatric applications (chronic diseases, immobilization, cystic vibrosis, osteogenesis imperfecta)


 * rehabilitation / physiotherapy


 * sports


 * space research / bed-rest studies


 * Galileo Dumbbell


 * comparisons and summaries

ISMNI recommendations for reporting whole-body vibration intervention studies

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Literature

 * Albasini, Krause, Rembitzki: "Using Whole Body Vibration in Physical Therapy and Sport: Clinical Practice and Treatment Exercises", Elsevier Health, 2010, ISBN 978-0-7020-3173-1