Aliens: Fireteam Elite

This achievement requires you to get jumped/knocked down 5 times in one mission by the larger/elite enemies (I was jumped by Prowlers and by Warriors when I got this achievement - I don’t think you get jumped by Bursters or Spitters) which start a QTE (quick-time-event) button-press.
You can NOT get this QTE if you’re run-at or sneaked up on by the standard Xenos or cannon-fodder, so watch out for the big Xenos to get the opportunity, and you can happily just mow down all others while you’re looking for them.

The easiest mission to get this achievement on is the first mission of the game.
Start your game on Casual difficulty, on a Private lobby (so you’re playing with the synths, Alpha & Beta). Casual difficulty means you get the most time to react to the QTE, and the Xenos won’t insta-kill you when they grab you either. The only downside of the synths is that they will shoot at all Xenos (and do decent damage), so there is a possibility that they’ll take out the Prowlers or Warriors before you can get the QTE. You will need to have experienced 3 QTEs before you get to the final part of the mission where you have to call the lift and hold off Xenos for 120seconds with the timer on-screen. If you start this section of the mission WITHOUT having completed 3 QTEs so far, you will need to restart the mission as there are 2 further QTE opportunities during the firefight as Warrior Xenos will rush you as part of the waves, the first at about 75-sec to go and the second when there’s about 30-sec to go. The voice-in-your-ear, Herrera, will also ‘announce’ their arrival.
Simply let the Warrior approach you (Casual difficulty should mean that you’re able to tank any acid damage/swipes whilst putting yourself in the path of the Warriors) and the Warrior will pick you up to start the QTE. As soon as the Warrior starts to pick you up the 5th time of the mission, the achievement should unlock (mine did, prior to me having to complete the button presses).
Spoiler:

The spawning of Warriors and Prowlers is random, so I can’t write a guide that says “go to this corner, get jumped etc” as every time you run the level it’s slightly different. The only thing guaranteed is the 2 Warriors in the last firefight.

TL:DR - walk up to 5 Warriors or Prowlers during a mission to get ‘jumped’ and start a QTE (button-press).

An alternative method to get this achievement without really having to boost it is if you got the challenge card Beautiful butterflies.

This card changes all the runner enemies into weaker versions of prowlers which means the majority of the enemies will now be able to jump on you and you can get this in the first few minutes of a level if you stand around or complete the level to work towards completing overwhelming confidence achievement for completing 25 missions with a challenge card active and i got jumped about 10 times it was a bit tricky to complete as i was low level.

Here is a video if you want a visual reference