Good lord - you should never be doing 50 reps! 30 reps is still considered way, way "low weight, high reps." High weight, low reps you are talking 8 to 12 reps.

Is it better to do 30 reps at a higher weight or 50 reps at a difficult but doable weight?

You don't have a high pain tolerance -- sounds like you have a LOW pain tolerance and can't step up your exercise level to where it needs to be to get fitter and to feel the after effects.

Your trainers didn't push you hard enough. You can and should be upping your weights if you aren't seeing progress, but you saying you could "hardly finish" more difficult exercises makes me think you have hit a mental wall and you're not going to push yourself anymore. If that's the case, you will not see improvement on your weight loss and you won't get sore muscles, period. Both weight loss and soreness come from pushing yourself past your current plateau. If you are stopping yourself from pushing due to perceived pain, you need a trainer who will push you and open your eyes to see you CAN complete much harder exercises.

But also, the reality is that if you're never feeling sore and you're not moving up in the weights you're using, you just not working yourself hard. You're not. If you want to keep working out the way you have been, at least start bumping up the weight by a few pounds and see how you feel afterward.

High reps/low weight is a very outdated notion of weight training for women. If you want to build muscle and get stronger, you need to do higher weight/fewer reps. Absent some kind of hormone imbalance, you won't get bulky from that.

Maybe you have a high pain tolerance and just don't feel the soreness.

I wouldn't worry about it. Feeling sore doesn't sound like a good workout goal to me.

NP here - I have gone through various phases of feeling sore every day, to never feeling sore no matter how hard I was pushing myself. I think to some degree it's a personal / physiological (? or physical ? ) thing, and also somewhat related to the types of movements you are doing.
I have also done bodypump for years, and gradually built up my weight selections as it does emphasize high reps/low weights. What really kicked me into gear was combining bodypump with a boot camp style class that emphasized heavier weights and fewer reps, also different styles of movement (ie more functional fitness and full body moves vs isolation). The heavier weights have NOT caused me to bulk up (on the contrary, they magically melted away that last stubborn 10 lbs).
If your friends are always lifting waaay too much weight, or pushing themselves intermittently, they will be more sore than you are, next day. Doesn't mean they are in better shape or working harder, necessarily.
Try a totally different class, not just a different instructor, to really give your muscles a shake up (ie swimming instead of boot camp, kickboxing instead of spin, etc).

OP again

I have worked out with trainers but dont feel any different after those workout, even when they seemed incredibly hard and I could barely complete the exercises. I cant afford a trainer currently and sp I generally attend classes, and that is where the variety comes in bc different instructors have diff styles and routines.

I have always been told I have good form.

I was always told and read that high reps/low weights is the best way to get lean and strong, as opposed to heavy weights and low reps, which can create more bulk (which I really dont want).

I have done boot camp style classes, weights only, kick boxing, circuit-training, body sculpting, etc. I still can barely do 10 push-ups.

Yeah, you need bigger weights if you want to break down and then build up new muscle. Or, you could do something your body doesn't do often and that might do it. I did a ropes course thing this weekend with my kid, and it was a blast. Didn't feel a thing while swinging through the trees except exhilaration. But the next morning? Ouch.

10 lbs is not a lot. You are not as strong as you think you are. Change it up and lift heavier weights. Lower reps and heavier weights.

I was a dancer in my youth and have been exercising my whole life. If I'm not sore the day after a workout, I'm disappointed. Muscle soreness is the sign that your muscles are building up.

Maybe it's your form? Maybe you need some variation - like using a kettle ball or doing plyometrics or pilates? Maybe you have a low tolerance for what feels "hard" while you're working out.

Perhaps you should work with a personal trainer for a few sessions to see if a trainer can take you to the next level, where you really feel those muscles working and 10 lbs. feels too easy.

OP again

When I say I've been doing the same types of things, there have been variations but they are all within the "light" weights/high reps world - squats, lunges, biceps curls, shoulder press, etc. I dont do it every day, as I have cardio days as well (spinning, zumba), but the weights is generally some variation of the same traditional exercises.

Also, while I have been using the same weights (roughly) for years, it is still challenging each time and if I find lifting 10lbs is easy, I go up to 12 or 15. Its just that 10 remains hard - to where I have trouble completing the exercises.

I've been exercising/lifting hard for a couple years and yes, I still get really sore. And some of my friends that workout just as hard don't. It is not a good gauge for how great of a workout you are getting. Results are.

ou said you've been lifting the same 5-15lbs for years. It sounds like you're not progressing because you've been doing the same thing for way too long. Your body will acclimate to the challenge and you won't get nearly as much out of it. You should be changing your routine every 4- weeks unless you're in maintenance mode. And even then I would just out of boredom.

I'm relatively new to exercise (year and a half), but the only times I feel sore, are if I try something new (or haven't done a particular exercise in a long time)

A new class, some new exercises with a trainer, etc. Maybe the day after doing hill sprints, if I haven't done those in a while. I don't think you're doing anything wrong - some of us just have different muscle recovery rates. If you know you're getting more fit and strong, that's what matters more than soreness.

But if 5-15lbs is easy for you, you should increase it. Keep pushing yourself once something becomes not-so-difficult.

I have been working out regularly since I was 18 (am now 35). I do a body sculpt/body pump class/boot camp 1-3x a week. The classes are always difficult and I challenge myself with the weight, often to where I have a hard time completing all of the reps, but i just dont get that sore feeling the next day like many of my friends. They are always complaining (in a good way)how they can barely move and the instructors are always saying "you will feel this tomorrow!" but I just never do.

Despite my years of exercise, I am still overweight due to a combination of genetics, poor eating, and 4 close together pregnancies. So while I am relatively strong, I am certainly not a body-builder or super fit. I just feel like I am not getting anywhere. I have been lifting the same 5-15lbs (depending on muscle) for years.

What am I doing wrong??