Factors That affect numbers of burnt calories during exercise:

We Can't say " If you ran 30 min. you will burn 300 calories or if you lifted for 10 min. you will burn 100 calories " . This is because there are many factors that determine and affect the number of calories you are burning during the exercise , and those factors are:

A- Physiological Factors: 

1- Age " middle aged tend to burn more calories than extremities because of muscle content " .
2- Sex " males are more likely to burn calories more than females " .
3- Height .
4- Muscle mass of the body " Important factor , the more muscle >> the more calories you burn " .
5- Total body weight .
6- Basal metabolic rate " BMR "
7- Genetics .

B- Personal variability:

 

1- Intensity and effort during the exercise .
2- Experience at the exercise  .
3- Baseline fitness level .

C- Workout factors :

1- Length of the workout " the longer workout >> more burnt calories " to certain limit . . 
2- Intensity of the workout .
3- The group of Muscle used in the workout " squats burn calories more than crunches " .
4- Weights " heavy weight >> more burnt calories and vice versa " .
5- Type of the Training " hard or just lifting " .
6- your rest period " the more rest , the less burnt calories " .

D- Other factors:

1- Disease the increase BMR " thyroid disease " .
2- Level of stress .
3- Sleep status : " The better and enough time of sleep the more calories you are going to burn during your workout " .
4- Cortisol level .

According to the previous factors , number of calories burnt during an exercise will vary from another person to another " up to 90% variation " .
and another word i'd like to say : Don't focus on the number of calories you are burning during your exercise , just do it regularly because many exercises have benefits for the body more than calorie burning like walking , stretching and even yoga .

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