Jörn Rittweger

Vibration as an exercise modality: how it may work, and what its potential might be

Whilst exposure to vibration is traditionally regarded as perilous, recent research has focussed on potential benefits. Here, the physical principles of forced oscillations are discussed in relation to vibration as an exercise modality. Acute physiological responses to isolated tendon and muscle vibration and to whole body vibration exercise are reviewed, as well as the training effects upon the musculature, bone mineral density and posture. Possible applications in sports and medicine are discussed. Evidence suggests that acute vibration exercise seems to elicit a specific warm-up effect, and that vibration training seems to improve muscle power, although the potential benefits over traditional forms of resistive exercise are still unclear. Vibration training also seems to improve balance in sub-populations prone to fall, such as frail elderly people. Moreover, literature suggests that vibration is beneficial to reduce chronic lower back pain and other types of pain. Other future indications are perceivable.

Bone-muscle strength indices for the human lower leg.

This cross-sectional study is based on images from the lower leg as assessed by peripheral quantitative computer tomography (pQCT). Measurements were performed in 39 female and 38 male control subjects and 15 female professional volleyball players, all between 18 and 30 years of age. The images were obtained at shank levels of 4%, 14%, 33%, and 66% from the distal end. Bone and muscle cross-sectional areas, and the bones density-weighted area moment of resistance and of inertia were assessed. From these, muscle-bone strength indices (MBSIs) were developed for compression (CI = 100. bone area/muscle area) and bending (BI = 100. bone area moment of resistance/muscle area/tibia length). Significant correlations between muscle cross-sectional area and bone were found at all section levels investigated. The strongest correlation for compression was observed in the sections at 14% (correlation coefficient r = 0.74), where 4.10 +/- 0.46 cm(2) bone, on average, was related to 100 cm(2) muscle. The compression index (CI) at the 14% level was independent of the tibia length. Interestingly, the 15 athletes had significantly greater CIs than the control subjects. This is most probably due to the greater tension development in the athletes. The highest correlation for bending was for anteroposterior bending at 33% of tibia length (r = 0.81), where the area moment of resistance, R, was on, average, 4.21 +/- 0.54 cm(3)/100 cm(2) muscle/m tibia length. Analysis of the bones area moment of inertia showed that buckling is a possible cause of bending at the 33% and 66% levels, but not at the 14% level. No gender differences in MBSI were found. Likewise, age was without significant effect. The data show that bone architecture depends critically on muscle cross section and tension development. Moreover, bone geometry (e.g., the tibia length) influences the geometrical distribution of bone mineral, as it was found that long bones adapted to the same compressive strength are wider than short ones. We conclude that MBSIs offer a powerful diagnostic tool for bone disorders and may contribute to improving the treatment of bone metabolic and other diseases.

Oxygen uptake during whole-body vibration exercise: comparison with squatting as a slow voluntary movement

Abstract. In this study we investigated metabolic power during whole-body vibration exercise (VbX) compared to mild resistance exercise. Specific oxygen consumption (% MathType!MTEF!2!1!+-n% feaaeaart1ev0aqatCvAUfKttLearuavP1wzZbqedmvETj2BSbWexLn% MBbXgBcf2CPn2qVrwzqf2zLnharyWqVvNCPvMCG4uz3bqee0evGueEn% 0jxyaibaieYlf9irVeeu0dXdh9vqqj-hEeeu0xXdbba9frFj0-OqFfn% ea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs0dXdbPYxe9vr0-vrn% 0-vqpWqaaeaabiGaciaacaqabeaadaqaaqaaaOqaaiqbdAfawzaacan% Gaee4ta80aaSbaaSqaaiabbkdaYaqabaaaaa!386A!

Is muscle power output a key factor in the age-related decline in physical performance? A comparison of muscle cross section, chair-rising test and jumping power.

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Reproducibility of the Jumping Mechanography As a Test of Mechanical Power Output in Physically Competent Adult and Elderly Subjects

n) and subjectively perceived exertion (rating of perceived exertion, RPE; Borg scale) were assessed in 12 young healthy subjects (8 female and 4 male). The outcome parameters were assessed during the last minute of a 3-min exercise bout, which consisted of either (1) simple standing, (2) squatting in cycles of 6xa0s to 90° knee flexion, and (3) squatting as before with an additional load of 40% of the subjects body weight (35% in females). Exercise types 1–3 were performed with (VbX+) and without (VbX–) platform vibration at a frequency of 26xa0Hz and an amplitude of 6xa0mm. Compared to the VbX– condition, the specific % MathType!MTEF!2!1!+-n% feaaeaart1ev0aqatCvAUfKttLearuavP1wzZbqedmvETj2BSbWexLn% MBbXgBcf2CPn2qVrwzqf2zLnharyWqVvNCPvMCG4uz3bqee0evGueEn% 0jxyaibaieYlf9irVeeu0dXdh9vqqj-hEeeu0xXdbba9frFj0-OqFfn% ea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs0dXdbPYxe9vr0-vrn% 0-vqpWqaaeaabiGaciaacaqabeaadaqaaqaaaOqaaiqbdAfawzaacan% Gaee4ta80aaSbaaSqaaiabbkdaYaqabaaaaa!386A!

Structural analysis of the human tibia by tomographic (pQCT) serial scans

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Structural analysis of the human tibia in men with spinal cord injury by tomographic (pQCT) serial scans

n was increased with vibration by 4.5xa0ml·min–1·kg–1. Likewise, squatting and the additional load were factors that further increased % MathType!MTEF!2!1!+-n% feaaeaart1ev0aqatCvAUfKttLearuavP1wzZbqedmvETj2BSbWexLn% MBbXgBcf2CPn2qVrwzqf2zLnharyWqVvNCPvMCG4uz3bqee0evGueEn% 0jxyaibaieYlf9irVeeu0dXdh9vqqj-hEeeu0xXdbba9frFj0-OqFfn% ea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs0dXdbPYxe9vr0-vrn% 0-vqpWqaaeaabiGaciaacaqabeaadaqaaqaaaOqaaiqbdAfawzaacan% Gaee4ta80aaSbaaSqaaiabbkdaYaqabaaaaa!386A!

Skeletal muscle oxidative function in vivo and ex vivo in athletes with marked hypertrophy from resistance training

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Muscle tissue oxygenation and VEGF in VO2-matched vibration and squatting exercise

n. Corresponding changes were observed in RPE. There was a correlation between VbX– and VbX+ values for exercise types 1–3 (r=0.90). The correlation coefficient between squat/no-squat values (r=0.70 without and r=0.71 with the additional load) was significantly lower than that for VbX–/VbX+. Variation in specific % MathType!MTEF!2!1!+-n% feaaeaart1ev0aqatCvAUfKttLearuavP1wzZbqedmvETj2BSbWexLn% MBbXgBcf2CPn2qVrwzqf2zLnharyWqVvNCPvMCG4uz3bqee0evGueEn% 0jxyaibaieYlf9irVeeu0dXdh9vqqj-hEeeu0xXdbba9frFj0-OqFfn% ea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs0dXdbPYxe9vr0-vrn% 0-vqpWqaaeaabiGaciaacaqabeaadaqaaqaaaOqaaiqbdAfawzaacan% Gaee4ta80aaSbaaSqaaiabbkdaYaqabaaaaa!386A!

Torsion and Antero-Posterior Bending in the In Vivo Human Tibia Loading Regimes during Walking and Running

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