Crikey - some intimidating numbers flying around in this thread...
From the other end of the spectrum I've been making more of an effort recently; partially out of insecurity / vanity and partially due to the knowledge that I'm aging towards solitude in an era of diminishing social care.
I've played with dumbells on and off but never "seriously" and have never seen any improvements in my potato-body-with-matchstick-arms shape. Problems have typically been that I find isolated exercises boring while I've always had issues with my neck and tension headaches.
The former problem has been helped by making the exercises more interesting by combining numerous into one cycle, while the tension headaches have been pretty much elimated by post-exercise traction courtesy of dangling by my arms off a beam in the house.. usually with a satisfying accompanyment of pops and cracks
For a while I've been doing a DIY lift with dumbells that involves various movements to get them from hanging by my sides to above my head and back again. I'm also trying to supplement this with overhead tricep extensions since these don't see much action otherwise, press-ups and renegade rows..
I find the press-ups less appealing, however have made good progress from being literally unable to do any when I was younger to managing 10 now; not terrible relatively-speaking, considering I'm carrying a fair bit of excess upper-body mass.
The renegade rows are great for seemingly exercising everything (and are correspondingly punishing) however I've had problems in the past with over cooking it and pulling muscles in my neck and core. I could really do with some lighter weights for these and can't be bothered to mess about with the 1.5 sets of dumbells I have (although would pick up another set if I could find some locally - irritatingly saw some apparently discarded outside a house some time ago but it was impractical to collect them).
There's certainly no informed, planned training regime (I just do a few exercises throughout the day when I feel like it) and it's probably not a very well rounded or efficient approach, however for the first time ever with weights I've actually seen some improvements..
My arms feel bigger and my muscles now actually limit the range of movement if I fold my arm back on itself at the elbow. My upper arms now fill out T-shirt sleeves fairly convincingly rather than looking like a broomstick hanging out of a wizard's sleeve and I can feel clothes are tighter around my shoulders / neck / upper-chest area; a much more positive feeling than the usual growing tightness around the dad-tits and belly.
If I flex my arms there's actually visible definition to the biceps while before the area was literally flat with barely any visible difference between relaxed and tensed states. I'm evidently physically stronger too, as I notice less issue moving specific, heavy household items about than I have in the past.
While I'm probably less muscular / strong than average it's great to have made some improvement and it's given me something positive to focus on while I struggle with my diet and degrade otherwise through age and weight gain. I'm hoping I can continue to make gains and maybe improve my aesthetic more when I eventually manage to get my eating under control / get out on the bike more over the summer.
It's nowt compared to those who do this sort of stuff "properly" but nevertheless nice to see what can be achieved at home with a set of weights that probably cost about as much as a month's gym membership