WHAT EFFECT DOES STRENGTH TRAINING HAVE IN A DIET?
The research group around William Kraemer from the USA investigated the effects of strength training with weights as part of a weight loss program.
The study examined fat loss, muscle maintenance achieved over the same period of time and the effects on the basal metabolic rate through endurance training on the one hand and strength training on the other.
34 overweight but healthy men were divided into four different groups to determine the optimal strategy for weight loss. One group simply went on a diet without any accompanying exercise program, i.e. was physically inactive. The second group did endurance training three times a week, the third group did a combination of strength and cardio training three times a week. The fourth group did neither exercise nor diet and served as a control group. As with all studies in which William Kraemer involved so far, the study variables were properly monitored and a meaningful training program was created for the test subjects.
The experiment lasted a total of 12 weeks. After this period, all subjects were checked again. All three groups that had reduced their calories lost the same amount of body weight, 9 to 10 kg. However, there were differences between the groups in terms of the percentage composition of the body tissue that was broken down, i.e. how much fat and how much muscle was broken down.
RESULT
The group without exercise lost 69% of its weight in the form of fat (so 31% was muscle), while the group with an accompanying endurance program lost 78% of the weight lost in the form of fat (so 22% was muscle). The difference between the two groups was therefore hardly noticeable.
The third group, which did strength training and cardio training as part of the diet, lost practically only fat and no muscle mass at all: 97% of the 9.9 kg weight loss was in the form of fatty tissue. This means that this group lost around 9.6 kg of pure fat in a period of 12 weeks. A result that can almost be described as sensationally good, which any trainer who works daily in the gym with athletes who want to lose weight can confirm.
SEVERAL STUDIES HAVE ALREADY CONFIRMED THE EFFECTIVENESS OF STRENGTH TRAINING DURING REDUCTION DIETS.
These results confirm earlier studies with female test subjects, according to which a strength training program should be the focus of any weight loss program. Surely everyone knows the poor souls in the gym who spend hour after hour on the cardio machines in the center with the goal of reducing their body fat percentage. It seems as if these people simply have too much time. Weekly training sessions of 7 to 10 hours are not uncommon for such people. Muscle training is categorically rejected by these die-hard "cardio fetishists" because "it only builds muscle, but doesn't lose fat - I want to lose weight."
Based on the data now available, it can be assumed that these fitness athletes will indeed lose weight just by doing cardio training. However, they will lose practically as much fat-free mass (i.e. muscle) as if they did not exercise at all. Not exactly a motivating prospect - so much work for nothing.
To clarify once again: building muscle while reducing calories (i.e. as part of a diet) is almost impossible; it is always just about maintaining muscle mass. Whenever you reduce calories, your body not only uses fat but also skeletal muscles, which are gradually broken down. The only solution to stop this process and thereby indirectly promote fat loss is muscle training on machines or with free weights. This creates a growth stimulus for the muscles being used, which, although not answered by muscle building as part of a diet, effectively prevents the breakdown of the hard-earned muscles. This indirectly forces the body to draw even more on its fat reserves, which ultimately increases fat loss.
STRENGTH TRAINING INCREASES YOUR BASE METABOLIC RATE AND THEREFORE INCREASES FAT LOSS FOR UP TO 36 HOURS AFTER EXERCISE.
In addition, previous studies have shown that the afterburn (the increase in energy turnover at rest, even after exercise) after intensive strength training is significantly higher and also lasts longer than with any form of endurance training, which is attributed to the energy-intensive protein synthesis processes. BASE SALES INCREASES OF 4 TO 7% can be detected over 24 to 36 hours after strength training.
In contrast, during endurance training at low intensity (fat metabolism training), this afterburn is negligible. Strength training therefore indirectly promotes fat burning in two ways, even if no fatty tissue is attacked during training.
It is to be hoped that the study results, which are now available in sufficient numbers, will be passed around among trainers and athletes so that there is finally clarity about how to set priorities in the area of sport when dieting: strength training + endurance training is the ideal combination for achieving optimal results when dieting. If you have to limit yourself to one of the two types of training (for whatever reason), weight training is always preferable to cardio training.
CONCLUSION:
ESPECIALLY AGAINST THE BACKGROUND OF THE CONSTANTLY INCREASING NUMBER OF OVERWEIGHT PEOPLE IN WESTERN INDUSTRIAL NATIONS (UP TO 50% OF THE POPULATION IN GERMANY, UP TO 70% IN THE USA), STUDIES SUCH AS THE PRESENT ONE ARE TO BE WELCOME IN ORDER TO FINALLY CLARIFY WHAT AN OPTIMAL EXERCISE PROGRAM FOR WEIGHT LOSS AS PART OF A DIET SHOULD LOOK LIKE.