I am a overweight woman of 38 years old (BMI 32,71). So 7 weeks ago, on October 2nd, I started a weightloss challenge at the gym. At first I had no physical condition at all, I started with 5 minutes on the crosstrainer, today was the first day that I went for 30 minutes and a 5 minute cooldown. I always select total body workout, in which it says that I should start and cooldown at a pace between 3 and 5 km per hour and in between I have to go at my own pace, concentrate on pushing with my arms, pulling with my arms, use my lowerbody only, go backwards or keep my speed above 8 km/per hour and then between 3 and 5 km per hour again.

Today for the first time I got up to a speed of 14.9 km/h and my heart rate went up to 175 beats per minute! According to the formula of Tanaka my maximum heart rate is 181.4 beats per minute, so 175 is very close, is that dangerous?

There is no formula that applies to anything apart from the rest of your health, so we can't answer this. A healthy person can get away with all sorts of stressors that could kill an unhealthy person. If you haven't had a full checkup, do so, and discuss your exercise regime.

Your bmi indicates you are extremely overweight. Leads me to believe you should not be starting on a weight loss programme on the crosstrainer but work up to it gradually. What is this 'tanaka' formula?

My understanding is that any weight loss program should not be undertaken for an overweight person without first checking with your doctor.

Your bmi indicates you are extremely overweight. Leads me to believe you should not be starting on a weight loss programme on the crosstrainer but work up to it gradually. What is this 'tanaka' formula?

My understanding is that any weight loss program should not be undertaken for an overweight person without first checking with your doctor.

https://en.wikipedia.org/wiki/Classification_of_obesity

I don't even have severe obesity, that starts at 35, so you are wrongly informed.

Maximum Heart Rate Calculator (http://www.shapesense.com/fitness-exercise/calculators/maximum-heart-rate-calculator.aspx) if you want to know about Tanaka's formula.

Here in The Netherlands we don't have the culture of getting check ups with your physician, before you go tot the gym, because we don't have such a huge sue and claim culture as in the US. It is totally normal to do whatever you want, if you are completely healthy, don't suffer from diabetes, don't have high blood pressure, don't have heart failures or anything at all, if you are class 1 obese, like I am. This group is especially for obese women and if I should get a heartattack at the gym, there is an AED there and someone can call an ambulance. If I would have a heart attack right now, I would die, because I am home alone and live by myself.

In the past I tried to lose weight before and it coincidentally came up when I went to see her for something else that I was trying to lose weight. So she asked me if I was also doing exercise and she said good.

I did need a statement from my doctor that it was okay for me to go scuba diving and I got that statement and since scuba diving is a lot more dangerous than doing exercises in the gym, I know that I am okay to participate in this programme.

I did went to my physical therapist recently, because I had lower back pains, she even advised me to start exercising, so I even took pictures of all the equipment in the gym to discuss with her which equipment was suited for me. She said everything except for the step device, because I would use my hips too much for that one, so that is what I am doing, everything except for the steps. I danced salsa for years and I danced it four times a week, but I got overstrained because of the combination of my job and my father's illnes, he died of cancer, tomorrow two years ago. I gained all this weight in the last four years. Both my doctor and my physical therapist are just like me hoping that I can start salsa dancing soon again. I went to a party a few weeks ago, but I am completely out of breath after only one song, while a few years ago, I could dance from 10.00 pm till 4.00 am with barely any breaks. I want to go back to that shape again, so I started with this programme at the gym to gradually get back in shape again. I really hate exercising in the gym, but I really love salsa dancing!

Litigious culture or not, before you started or not, you wanted to know if you should worry, and there is no way to know without knowing your entire medical history.
Charts, apps, and formulas you find online aren't really meaningful, given all the variables of health one person can have.
Offhand I would say that if you don't feel weak, dizzy, short of breath, or a tight feeling high on your chest, not necessarily on the left, then don't worry.

Misspurple do not lead me down the garden path here. I live in Canada not US. I am not SADLY informed. I had no idea where you live, your healthcare medical history or whatever. You asked a question, I answered.

stick to walking and salsa dancing.