Since HP Hooded Cobra already gave you the reality check, I'll give some practical advice. I don't know your physical, mental and emotional condition but consider this: they need to be much further than any amateur athlete. You need to be in pair with pros in terms of stamina and endurance. If you aren't, you need to prepare and build solidly.
I don't pretend to know all the fields where you are challenged the most but two are endurance running and rucking, with or without extra weight:
• https://www.goruck.com/event-training-plans -- for this a strong back and a strong core are what make all the difference
• Iron Shirt Qi Gong
Extra weight ranges a lot. There's no standard between one country and another. Remember that those aren't usually done when you're fresh and sound but when you're sleep deprived and have been already involved in other activities both mental and physical/practical, in order to test skills such as endurance, stamina, durability, alertness and stress management.
Why Iron Shirt Qi Gong?
Iron Shirt Qigong
Iron Shirt Qigong was originally used by Kung Fu practitioners to improve internal power and resistance through the development of Qi within their organs, tendons and bones. Mastery of such was required before any actual fighting techniques were taught. This Qigong allowed them to withstand blows to their vital organs with the analogy with one without training experiencing the strike as steel and one with training experiencing such as plastic. The Qi protects.
This Qigong helps to properly align and empower the structure of the body through the creation of a Qi belt. Organs and glands are detoxified and worked with packed Qi to help cushion from external trauma and benefit from the increased Qi pressure. The fasciae sheets of the body are also packed with Qi to further protect the body with the added bonus of burning fat. One also learns how to properly root oneself to the Earth to release and absorb energy. Bone marrow is strengthened which enhances the blood and thus the lifeforce. Overall there is an increase flow of Qi and feeling of well-being. This Qigong teaches one Qi control.
The practices of the above can be found in Iron Shirt Chi Kung I, II and III by Mantak Chia.
Source:
The Taoist Path to Immortality, HP Lucius Oria
When you test for the ASVAB (or whatever the test is called for the US Navy), you need specific scores to be selected for the branch you're passionate about. Research which are those and prepare according so you get them without fail.
Navy Seals are airborne too, of course, which means they go to jump school. They do both day and night jumps, trained to do them with a static line up to accelerated free fall from 9500 feet. The course lasts 3 weeks. In my opinion, it'd be better to prepare in advance a protection working so the risk of accident during a descent is completely negated.
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luis said:
And you can't really meditate if you are in those places...there are other jobs out there that are much better for a SS. One can always you magick to get them.
Where there is a will, there is a way. If you want to meditate, you will put your brain to work and find the right places and the right times to do it without issue. The hardest is during training stages but there's always a way. Outside of training stages, is MUCH easier to have the correct timing.