Associations between age and jump performance among special weapons and tactics team operators

Lower-body power is essential for Special Weapons and Tactics (SWAT) unit operators when performing many occupational tasks, such as breaching, casualty extraction and seeking cover. In interesting aspect of SWAT teams are sometimes very diverse age demographics. In many instances, there are a very wide range of operators from various age groups who must be able to adequately perform their occupational duties in order to successfully complete their mission. Generally, some if not most of these occupational duties are influenced by an individual's ability to produce muscular strength and power. However, the relationships between age and lower-body power within this population have not been fully explored, especially in tests that require multiple efforts.

Purpose: The aim of this study was to examine the relationship between age and vertical jump performance among multi-jurisdictional SWAT team members. 
Methods: Seventeen (n = 17, age 35.5 ± 5.9 years; HT 181.5 ± 8.4 cm; BM: 96.2 ± 13.1 kg) male police officers belonging to a multi-jurisdictional SWAT unit participated in this study. Multi-jurisdictional SWAT units are generally a collective group of SWAT operators from several smaller departments who combine forces and respond to the needs of all the law enforcement agencies they serve. After anthropometric data and self-reported age were recorded, all officers performed 4 consecutive vertical jumps on a contact mat. Data collected from this assessment included average vertical jump height for the 4 jumps (VJ height) and the average ground contact time between jumps. A Pearson correlation was used to determine if significant relationships (p < 0.05) existed between age, VJ height, and ground contact time. 
Results: No significant relationship (r = 0.245, r2 = 0.05, p = 0.97) was found between age and VJ height among the officers. However, a strong positive correlation between age and ground contact time (r = 0.712, r2 = 0.50, p = 0.001) was found.
Conclusion: The results of this study reveal that while VJ height did not decrease with age. However, the results indicated that increased age was associated with a longer average ground contact time between the consecutive jumps. This suggested that older officers may have spent more time in contact with the ground to maintain the same jump height as their younger counterparts. This may be due to a greater dampening of the stretch-shortening cycle at ground contact among older officers.
Practical Applications: Older SWAT officers may utilize different jump strategies and rely more on concentric force production to achieve greater vertical jump heights in contrast to the utilization of stored elastic energy when ground contact time is reduced. Additionally, this may influence job performance by increasing the time to completion of power-based occupational duties. Therefore, it may be in the best interest of tactical strength and conditioning facilitators to identify and apply age-specific strength and conditioning approaches if possible.