Dumb S**T people claim about health and fitness
I don't claim to have all the answers in health and fitness but I do know quite a lot from having done a lot of things right, then doing them wrong, and then changing them up to do things correctly for me in the end. There is no one correct way but there are a lot of wrong ways and in the times of my life I have heard some really crazy excuses and bad advice from people over the years.
I feel as though I am qualified to have an opinion about this sort of thing because I was an elite athlete into my mid 20's then towards the beginning/ mid of my 30's I let myself go and then became a fat ass at around 250 lbs. Then something happened and I turned it all around in my 40's and currently I am sitting at around 185lbs, which is only 10 lbs higher than my genuine fighting weight when i was 22 years old.

I have no educational background to back any of this up but I have lived it and I think that is kind of important as well. Anyway, here are some seriously dumb things I have heard over the years
Cherly's salad dressing

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Cheryl was a college friend of mine. Cheryl gained the famous "freshman 15" and kept going. She was hefty and I kind of appreciated the fact that she knew this and was trying to do something about it. The problem with Cheryl was that instead of doing what we all know works, Cheryl tried to trick herself into eating believing that what she was doing was healthy rather than it actually being so. I was at dinner with her and a group of friends and even though nobody asked, she let us know her strategy for dinner and eating healthy.
She ordered a salad because salads are healthy right? This one definitely wasn't. It is a salad that had fried chicken strips on it sliced up, tons of croutons and cheese as well. Cheryl, in her delusional justification asks for the salad dressing on the side because as she says "that's where all the fat and calories are"
Sorry Cheryl, you are extremely wrong.
Not to mention the fact that Cheryl would dunk the bites of salad into the dressing basically drowning the stuff in it anyway and she went through more than one "on the side" when she was finishing her crazy salad that was probably more caloric than a double cheeseburger. Cheryl would never eat a cheeseburger... because they are "bad for you." I felt bad for Cheryl because her lies were only affecting her, not anyone else. We stopped trying to correct her because she had convinced herself that she was correct even though I think even she knew that she was dead wrong.
This video about giant taco salads comes to mind.
The last picture I saw of Cheryl she was still overweight, in fact she had gotten substantially fatter and I am not surprised. Lying to yourself about fitness is the worst kind of lie to do!
I have knee problems so I can't run
I have heard this more times than I care to report. It always comes when I am talking to people that do not regularly exercise and while I am not bragging nor did I bring it up I will talk about various runs I have done because that is what me and my group talk about.
Without fail, someone in the group who doesn't exercise will say something like "I would love to do that sort of thing, but I have bad knees." I look at them and have learned to hold my tongue but I know that 90% of the time, that person is overweight, has a borderline alcohol problem, and in no way has any doctor-confirmed "knee problems."

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If you are out of shape or fat or worse, both, and you go to do some sort of physical activity including and probably especially running, your knees and other joints are going to hurt. This does not mean that you have "bad knees" this means that you are out of shape.
I always say that "your knees hurt when you run because you don't run." My knees hurt after a break from running as well or if I overdo it such as was the case on my hill run 3 weeks ago. This was because it was more exercise than I am accustommed to, not because I have "bad knees."
The thing about self-prescribed "bad knees" is that if you continue to use that as an excuse to not do any exercise and instead pull up a barstool to the nearest put every night, you will eventually end up with genuine bad knees. Then you won't be able to do anything about it.
Both of these things really annoy me when I hear them because it's just so delusional and self-sabotaging. Cheryl could have been operating at a calorie deficit instead of trying to bullshit her way to a fake healthy meal, and the myriad of people with fake knee problems could have gone for a light run and worked their way up to being able to run but nah! It's easier to just sit and make up a fake reason why you can't do it.
These people almost always end up in the same place though and for many of the people out there if you find yourself having excuses to not do something healthy, well there is a good chance it can happen to you as well.
I will put more of these out there in the future, this is by no means the only dumb crap I have heard, but this is already 1000 words long