Osteogenic index of step exercise depending on choreographic movements, session duration, and stepping rate
- 1Sport Sciences School of Rio Maior, Rio Maior, Portugal
- 2Faculty of Human Kinetics, Universidade Técnica de Lisboa, Lisbon, Portugal
- Correspondence to: Rita Alexandra Santos-Rocha Escola Superior de Desporto de Rio Maior (Sports Sciences School of Rio Maior), Rua José Pedro Inês Canadas, Iote 1, r/c, 2040-326 Rio Maior, Portugal;
- Accepted 17 July 2006
- Published Online First 18 August 2006
Background: Step exercise has been promoted as a low impact physical activity recommended for the improvement of cardiorespiratory and muscular fitness. This recreational activity might also be recommended to improve bone health since mechanical load plays an important role in the normal development of the skeleton.
Methods: Our main purpose was to characterised 100 step sessions and to calculated osteogenic index (OI) according to Turner and Robling: OI (one session) = peak ground reaction force(BW)*ln(number of loading cycles+1).
Results: Main results (mean±SD) were as follows: OI was 12.0±0.8; peak ground reaction force (GRF) was 1.40±0.10 times body weight (BW); session duration was 38.6±8.3 min; stepping rate was 134.6±4.7 beats per minute (bpm); the movements performed most often were marching, knee hop, side leg, L step, and over the top; and the number of loading cycles was 4194.1±1055.2. OI and GRF increased significantly when stepping rate was higher than 135 bpm. This stepping rate might be used as a reference for higher intensity classes. A frequency of two to three sessions per week of step exercise is recommended.
Conclusions: Despite the benefits that have been stated when step classes are structured correctly and adapted to the participants, further research is needed concerning biomechanical load, exercise prescription, and injury prevention.
Published Online First 18 August 2006
There are no competing interests