This question has a long answer but it most definitely can be simplified!
I would like to mention that this is a topic where the title is slightly incorrect, as you can lose weight from exercise alone, however the process in which you do so is unsustainable and likely to fail. Studies that have shown exercise has produced meaningful weight loss, the participants burned at least 400 to 500 calories per session on five or more days a week. To achieve that, a 150-pound person would need to log a minimum of 90 minutes per day of brisk walking or 30 minutes of running 8-minute miles. Even if we manage to exert that much effort, our bodies often compensate by boosting appetite and dialling down metabolism, effects that over time limit how many pounds we shed, but this is touched later on so keep reading!
We all know that to lose fat you need to be in a CALORIE DEFICIT and to do this you must either expend or consume (or do both) more energy than the energy (food or drinks) you put in your body.
EEE - Exercise energy expenditure
DIT- Dietary intake thermogenesis
NEAT- Non-exercise activity thermogenesis
RMR- Resting metabolic rate or BMR
EA - energy availability
Exercise has this huge ideology that its sole purpose is for aesthetics and weight loss. Which is completely wrong and once you get to terms with this it will make your journey a whole lot easier. By framing exercise as penance, we’re unlikely to enjoy it or to keep doing it for very long. REMEMBER CONSISTENCY IS KEY!
I would also like to note that I am not promoting anyone to stop exercising. Exercise/physical activity goes way beyond weight loss. It’s been shown to reduce the risk of heart disease, stroke, cancer, diabetes, dementia, depression, colds, back pain , osteoporosis and premature death. It can also improve sleep, boost energy, fend off old-age feebleness and even enhance our sex lives
First, let’s clear up that exercise means when you purposefully put on your workout gear and dedicate a part of your day -usually an hour, to move your body. Other daily activities come under the name NEAT, non-exercise activity thermogenesis, and accounts for any movement that isn’t structured exercise. For example, walking the dog, pacing when on the phone, walking in the shops, cleaning. That one hour of exercise you do therefore only takes up ~4% of your day, versus NEAT (non-exercise activity thermogenesis) which accounts for around ~64%.
Another study which carefully tracked which carefully tracked how much people ate and moved after starting to exercise, found that many of them failed to lose or even gained weight while exercising, because they also reflexively changed their lives in other, subtle ways. Scientists studying the issue agree that most of us compensate for the calories lost to exercise by eating more, moving less, or both. Our resting metabolic rates may also decline if we start to lose pounds. All of this shifts us back toward positive energy balance, otherwise known as weight gain.
Those who exercise for weight loss in mind tend to reduce any other movement across the day. Its so common for people who have an office based job or sedentary lifestyle to see that 1 hour of exercise as “Job done” for the day, a box ticked and once done you can come home and sit on the couch, you might reduce the amount of NEAT across the day, i.e. order lunch vs going out to get it at lunch time because ‘you’ve done your hour gym session’. This decline in daily NEAT is likely to compensate for a reduction in more energy expenditure than if you were to do just your hour of exercise and no NEAT.
You don’t progress your workouts.
From an evolution stand point your body is built to be really good about defending its body weight. It doesn't want to change weight very easily. People that regularly exercise tend to build more efficient metabolisms, your body starts to expect the demands that you put into them and even when you don’t engage in exercise, your body still burns lots of extra calories.
Eventually a lot of people hit a weight loss plateau or gym progress plateau, meaning that they aren’t seeing increasingly better results they are just staying the same or losing progress. This is normal and usually just down to adaptation. Increasing NEAT during this time or altering calorie intake further will allow you to see results. If you want to further this make sure you are continuously increasing the intensity in the gym whether this is sets, reps, weight, time, tempo, durations, speed… (check out the infographic on metabolic adaptation here)
Compensating for your extra calories burnt
It is normal for you to have an increase appetite after working out. Your body goes through big changes during exercise, mini micro tears in your muscles, your heart rate is higher and so you burn more calories and uses up your glycogen stores which will in turn stimulate your appetite. It also dehydrates you and if you don't drink enough water before, during and after your workout, you're going to feel hungry. Researchers have therefore shown that those individuals who exercise consumed roughly about 90-125 additional calories each day when they exercised. This over time will add up. Individuals also commented on the fact that they felt as though they were able to consume more calories on the day they exercised as they has had ‘earn’ the food. Having this mindset surrounding exercise will not only hinder your process but also create negative triggers towards food and exercise that might lead to eating disorders or obsessive behaviour.
Exercise for your health and wellbeing and utilise that hour in the gym to maximise your strength, technique and cardiovascular fitness for overall health and longevity. Up you NEAT and track your calorie intake to make sure you are in a good enough calorie deficit so that you can achieve your fat loss goals.
If you are new to everything I wouldn’t start but throwing yourself into the gym. I would master your food consumption and calorie intake, become aware of the food and drinks you are consume and at what quantity. Pair this with increasing your daily step count, 2-3K more than you are doing now. After a couple of weeks of doing this start adding the gym (thats not to say don't start in the gym straight away if you're motivated, the key is just don't go in at 150% to then burn out and quit after week 1)
Remember, other external factors such as stress and genetics, age all will play a role in your fat loss journey!
If you are struggling where to begin or feel overwhelmed by the issue then please reach out to nutrifit coaching. Our platform is unique as you are guided through your journey with two health and wellness individuals vs one, collectively specialising in strength and conditioning, performance, fat loss and nutrition.