The first few months of lower body weight training move along fairly quickly because the improvement is more neuromuscular than muscular.
After the neuromuscular system wakes up and is ready for action, progress slows down a lot. Physical architecture, frailties, and age are of course possible obstacles too.
Lack of progress, and plateaus, can be discouraging with large muscle group strength. I think my max 1-rep deadlift has only increased by about 20 lbs in the past year. 2020 will improve by 10 lbs, maybe, because I am fighting ageing. Small muscles improve more quickly (eg arms, but even backs improve fairly quickly - pullups)).
In my experience, the aspects of fitness that improve most dramatically and quickly in the Maggie's Fitness for Life program are endurance and energy. Precious things. Two days of weights/wk is not enough for serious strength-building, but the part of our program with 2 days of calis and the 2 days of HIIT cardio will get you fit for most recreational activities like sports, day-long hill hiking, etc.
Any age or gender. Give it a try. Include the barbells. A good Christmas/New Year present to oneself is a badass sexy and highly functional physique but, God knows, it takes discipline. Nothing pleasant about it except the slow progress.
I have a retired friend who has taken on learning Mandarin as his retirement project. I'd rather face a nasty, ugly barbell.
