I am 105 kg, 185 meter high.. 50 years old.. almost every single morning I wake up with sore lower back and atiff legs and back. Including headaches that, if I don't do stretching, will get worse and only are treated with painkillers.. current mattress is foam with slated bed (adjustable).. have tried very firm mattresses too.. but nothing seem to help.. my wife is half weight and 1.55 m.. so possible looking at zip and link mattress.. can you let me know how to go about this.. happy to invest in bespoke made for whatever helps to give me right support throughout back.. sleep on my side on on my stomach mostly..