The shoulder bridge: gluteal engagement

Lie on the floor with your knees flexed (feet on the floor) and stick your fingers into the meat of your ass.
Squeeze your ass cheeks together as your method of engaging them  and not by trying to over extend your hips or play with your pelvis; keep that neutral.
Once that is mastered,  bridge the torso off the floor. At this stage, you , a friend or your trainer needs to feel your hamstrings. People who are “hamstring dominant and gluteal deficient will engage the hamstrings prior to moving” (McGill: page 195 Ultimate back Fitness).
This is the wrong pattern. The glutes should drive this action. To help  we can put our foot against your toes, and whilst asking you to squeeze your ass, we  can help your quads engage by lightly cueing from the knees ( so either a finger hook under the knee to gently pull them up, or if you know each other, a quad stroke ( to encourage the hamstrings to switch off) ).
Once you get  your  ass  engaging, “Boom” your back gets  a bit more resilient  and your squat gets better!
shoulder bridge

Be careful of your deadlift form: why sport science reports can mislead you

Much of the development of human movement comes from coaches comparing techinques. Better coaches hang out with other coaches, go on their courses, read their blogs, learn, analyse, video, and humbly put stuff up for criticism.  Many sport science papers purport to do the same thing. However, the only value of  a report of an experiment is, if you can reproduce the experiment yourself.
Do you remember those basic physics and chemistry experiments we did at school? We followed the exact doses, mixed , shook, heated and retreated to a safe distance. The instructions told us, how much, in what container , in what proportion. to what temperature.
This often isn’t the case in sport science journals. Sport scientists  casually say they are testing the efficacy of , say,  the deadlift and squat but often fail to explain what they mean. This frequently means back specialists often prescribe or ban  movements where there is no correct understanding about what the movement is and how to perform it. I often see clients who have been banned from performing movements they do well and perfectly, and being set drills and movements, which, clearly, the  instructor had not the faintest idea of the correct form or the correct mechanics .
The picture here is from a leading book on back issues and is supposed to be the correct form of the deadlift. It is, unfortunately not brilliant, (probably for all the best reasons), but, if you  deadlifted in this way, you would , eventually, overload your back ( as always, poor form needs to be mixed with  repetition and  escalating load weight  to be truly nasty).
This is not an attack on sport scientists ( I do that elsewhere). After all,  all research is useful , it is a plea to look for the instructions or method in the report you are reading. Can you reproduce what they did? If not, treat the information with caution.
We will post later the correct way to deadlift.