I am an instructor to., I don't ever recommend running to anyone in the beginning either. I leave it up to them depending on their level of fitness. Some people can pick it up right away, some can't. It also depends on how active a person has been throughout their life. But I will agree that it a lot of stress on the knees.
I disagree meeker, running is harder on the knees than simply carrying around extra weight on a daily basis. The fact is there is sound science behind recommending overweight individuals to not run, not just some blatant "fat people discrimination" on the part of the trainer. Like jerihurd said, running is extremely high impact - 25 pounds of extra weight puts 100 pounds extra load on your joints when you're just walking around, which shoots up to 250 when you run. That's a lot of wear and tear.
Biking, walking, swimming, and elliptical are all lower impact cardio activities.
But as always I say to get the most bang for your buck in the gym lift free and lift heavy (variations on squats, deadlifts, overhead pressing). It's way lower impact than any cardio activity regardless of how much weight is on the bar, and the degree to which it forces your body to adapt to stress burns waaay more fat over time than any cardio activity. Plus you build a lot of muscle, which again, helps you burn that much more fat. And in non-steroid-enhanced women (I'm assuming most if not all of you), it's dense, shapely, hawt muscle, not grotesque, veiny, boxy muscle.
Okay, weightlifting rant over.
While I agree that there are other really good, low impact workouts that are easier on the body than running and burn as many calories, I still say that if you want to run, then go for it. Start off slowly, wear good shoes, talk to your doctor and do some research on good form. I know that weightlifting works, and so I do it, but I never look forward to the weight room in the same way I look forward to a good run. I guess I would hate for someone to read this thread and use it as an excuse for not trying a workout they might really enjoy.
And as for wear and tear on the body, I think with every physical activity there is an inherent risk of injury. I totally blew out my knee on a bicycle and just last night I watched a guy throw his back out in the free weight room. Injuries happen in every sport. So do I think a person who wants to start running should avoid it because of a possible injury? No, I do not.
I wasn't saying you should avoid all activities that carry a risk of injury. My point was simply that most people who are overweight tend to be grossly under-prepared for the kind of stress running puts on their bodies. There are other lower-impact activities that will achieve the same results without wearing down the body. And I agree that everything has to be done with the right form, and sometimes this means throwing your ego aside.
If running is what gets you up and moving, then make sure you're prepared to do it right, and then do it.
I used to work with a trainer and I was about 305 when I started with them. They didn't want me running either but it was only because I didn't even have the endurance to walk far. so they had me work up my walking but then had me start jogging. I lost that endurance when I started gaining weight again, but I plan on starting jogging again soon. I say if you have the ability to walk comfortably than give it a try. good luck to you.
I currently am 116 pounds overweight. I have been working out since the beginning of the year. I tried running 5 months ago, and was discouraged that I couldn't. Since that time, I have strength trained, done a variety of cardio workouts, worked with the elliptical and the spin bike. So I decided to try running again. It's not easy, but it doesn't hurt like it once did. I'm by no means an expert on running, and not a doctor. I decided to do the Couch to 5K program by Cool Running, and so far I LOVE IT! It eases you into it. Small intervals, and increasing each week. I continue to stregth train even more, so that I do not hurt myself. I do not push too hard, or go to fast. I hope that it does not hurt me too bad in the future, because it feels great right now. I think it would be far worse for me to be unhealthy and severly obese for the rest of my life (as I'm only 32), than trying to run ... but everyone is different.
I too talked to my doctor before doing all of this. When I first began workouts, I had terrible knee pain - due to arthritis. I was told that it would most likely get better with the more weight I lost. So I stuck to my guns and my knees rarely hurt now.
Good luck with whatever you decide to do. Ease into it. The elliptical machines are a great way to start off!
I think the trainer is probably giving you sound advice, though he may be overly cautious, he was there with you in person and had a lot more information available to base that decision on than us (and as a fitness professional is potentially highly educated, a lot of the personal trainers are pretty much just people who happen to be in good shape, and may not be all that qualified really... but there are also a lot of them that have so much physiology education they are half way to being doctors).
Now the good news, even without doing a lot of running your ability to run will greatly improve as you get to a good bodyweight for your build. I ran for over a year without much improvement, seems like I couldn't handle much more than a mile, there was a bit of gradual improvement, my main exercise was weightlifting but I always felt like the goal isn't just to look good, it's to actually be a functional athlete (which running is kind of a symbol of), well, that slow progression in running started to take off after a while, when I started getting close to my goal weight and somewhat lean (still overweight) but I found the difference between being able to run a fairly fast 1.5 miles and running 3 miles, was about 10 lbs for me. At 217 lbs I could do a respectable 1.5 miles (probably less than 10 mins) and at 207, 3 miles was surprisingly easy (mostly the fact that I could do 3 miles non-stop at my natural pace is surprising).
So my own advice would be stick to ellipticals and bikes, weights, and diet, a little running if it's comfortable is fine, but it's probably going to be better and easier overall to progress in running once your weight is more in line with your body type (which may or may not fall into the 'ideal weight' range of BMI or other measurements). Conditioning in running is something that builds up quickly and fades quickly, but your weight will drastically limit your endurance, your lungs don't grow from exercise, it's more about the rest of your body not having to consume as much oxygen to feed your muscles to keep up the activity.
Running is a great workout, but it is very unforgiving on the knees and the lower legs. I was told by a DR when I had surgery on my knee that it was better to walk at a steady controlled pace then to run where your feet are pounding the pavement cause your trying to keep going.
I took his suggestion and walked 2.5 miles 3 days a week for about 1.5 months then got bored and started jogging alittle while staying in a controlled pace where I was going heel to toe. I started in May, in Sept I ran a 5K in 30mins. For the record I was 285lbs when I started and was down to 235lbs in Sept. Unfortunitly back to 240 but starting again now that its nice out.
I'm a Personal Trainer, and I kind of agree with what your PT said, although I don't agree with the way he told you
This is the route I take with an overweight client who wants to run
1. We undertake a weight management program that depletes weight that is safe (or safer) on the joints, we also introduce foods that will add to the clients energy
2. We undertake a postural and corrective exercise program that mobilses the joints and opens biomechanical pathways meaning bad technique and movement pattern do not get locked in and create problems in years to come
3. We build cardiovascular endurance on a non impact piece of equipment (spin bike)
Once the objectives have been achieved, then we can move on to running, although I mainly use metabolic resistance training with clients as my target market is in the "looking good" mindset which you can't really achieve with running alone