class: center .pv-6[ # Common parkour vault techniques, landing styles, and their effects on landing forces .center[📝] ] --- # What is parkour? - A sport or discipline that involves **traversing an environment** - Can focus on being utilitarian and quick, or artistic and expressive (or a mix!) - Influenced by a lot of other movement practises like dance or acrobatics, but does have some distinct **parkour specific movements** - Generally places emphasis on **soft, controlled** landings from jumps and other movements that involve leaving the ground --- # What are landing forces? - Also know as ground reaction forces or **GRF** - The harder you hit the ground, the harder the ground hits you back, according to [Newton's third law of motion](https://en.wikipedia.org/wiki/Newton%27s_laws_of_motion#Newton's_third_law) - For jumping, generally the focus is on two specific types of GRF: - Vertical .small[(vGRF)] - Horizontal braking .small[(bGRF)] --- # Vertical GRF How hard the ground pushes back up at you as you come down on it:  --- # Braking GRF How hard the ground pushes backwards as you push forwards on it:  --- # Why do we care? - The maximum or **peak GRF** in each direction experienced during a movement is a good indication of the level of stress it applies to the body - So generally, the greater the peak GRF you experience with a movement, the more likely it is to cause you injury --- # Landing forces in parkour - GRFs can be reduced by good landing technique and/or strong leg muscles - Parkour athletes (known as **traceurs**) are particularly good at this - This has been demonstrated in studies on drop landings and jumping with traceurs in comparison to athletes from other disciplines --- # Parkour vaulting - While good at jumping and dropping, traceurs also do a lot of other movements as part of their parkour training - One really important group of parkour movements are **vaults** - This study looked at three common parkour vaults: - Step vault - Dash vault - Kong vault --- # Step vault .center[<iframe width="800" height="450" src="https://www.youtube.com/embed/2knvpLwrQ2g" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>] .very-small[*Video courtesy of <a href="https://londonparkour.com" target="_blank">London Parkour</a>*] --- # Dash vault .center[<iframe width="800" height="450" src="https://www.youtube.com/embed/c1lVJ2SMyYs" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>] .very-small[*Video courtesy of <a href="https://londonparkour.com" target="_blank">London Parkour</a>*] --- # Kong vault .center[<iframe width="800" height="450" src="https://www.youtube.com/embed/qfevj-jwCuM" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>] .very-small[*Video courtesy of <a href="https://londonparkour.com" target="_blank">London Parkour</a>*] --- # Landing styles - Additionally, you can land a parkour movement in a number of different ways - This study picked two common landing methods: - precision landing - running landing --- # Precision landing .small[Landing two feet and coming to a stop:] .center[<iframe width="620" height="350" src="https://www.youtube.com/embed/66bY7ZURPYg" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>] .very-small[*Video courtesy of <a href="https://londonparkour.com" target="_blank">London Parkour</a>*] --- # Running landing .small[Landing one foot and continuing to run:] .center[<iframe width="620" height="350" src="https://www.youtube.com/embed/59i3xSE316I" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>] .very-small[*Video courtesy of <a href="https://londonparkour.com" target="_blank">London Parkour</a>*] --- # What was the aim of the study? - The study was interested in whether the GRFs for these common parkour vaults would be **similar or different** to those found in drop landings with either landing style - ...and whether they would also be similar or different to each other! - This could help assess the injury risk of performing these vaults with these landing styles --- class: img-right-full  # Data collection - 10 people performed a drop, dash vault, step vault, and kong vault with both landing styles onto a **force platform** that recorded the GRFs produced - These landings were analysed by two-way repeated measures [ANOVA](https://en.wikipedia.org/wiki/Analysis_of_variance) for differences, and by [intraclass correlation coefficients](https://en.wikipedia.org/wiki/Intraclass_correlation) (ICC) for reliability --- # What were the landing style differences? - Vertical GRFs **increased** for all movements when using a running landing compared to a precision landing - Braking GRFs increased for the kong vault and drop, but **decreased** for the step and dash vault with a running landing compared to a precision landing --- # What were the vault differences? - The **kong** vault always produced the **greatest GRFs**, usually by quite a lot - The **dash** vault always produced the **least GRFs**, but not always by a lot  --- # Results summary .small[Here are all the forces recorded, in multiples of bodyweight (BW):]  --- # Are these results reliable? .small[Generally, GRFs recorded across repetitions of each movement/landing style were at least moderately reliable ([ICC](https://en.wikipedia.org/wiki/Intraclass_correlation) > 0.5), but not always:]  --- # Why was this the result? - The **knee** is a big part of performing a good landing, but has to remain **stiffer** in single leg landings, meaning it can't help absorb GRFs as well - The kong vault **tilts** the upper body forward more than other vaults, which might affect how the hips and legs absorb GRFs - The dash vault lets a traceur **use their hands** behind them a lot more than other vaults, which may help control the drop and reduce GRFs --- # Why does this matter? - Although greater in running landings, the GRFs recorded in this study still **do not exceed** those seen in jogging, so remain **unlikely** to be immediately dangerous to traceurs - But, **repeating** these movements a lot may still add up and cause injury **over time** - When training very frequently or during long training sessions, traceurs may want to pick vaults and landing styles with lower GRFs or lower the repetitions of higher GRF vaults and landings styles in order to **control overall training intensity** and reduce injury risk --- class: center .pv-6[ # Thanks for reading! .center[📝 [Read the full study online by clicking here](https://jmablog.com/research/pkvs/read)] .center[.small[🔗 [jmablog.com](https://jmablog.com)]] ]