Based on the results, we can observe the effectiveness of the nutritional intervention in some aspects addressed in this study, especially regarding protein and calcium intake, in which the instructed groups showed an improvement in their intake profile. Positive results were also observed regarding physical activity level and quality of life, as the nutritionally instructed groups showed a tendency to perform better. The improvement of quality of life through better dietary patterns is already well established in the literature for this population. Oliveira et al. in 2019, noticed in a group of elderly women and men, that the physically active group had a direct relationship with higher quality of life when compared to sedentary individuals through analysis of the SF36 test22. Another study observed that a better dietary pattern and an individualized diet had a positive impact on the functionality and quality of life of the elderly23.
This association can also be observed in other studies. A 2018 study evaluated the quality of life of 407 elderly individuals, as well as their nutritional status and dietary parameters. This study indicated that elderly individuals who did not have good nutritional status, had no appetite or had a dietary pattern outside of their energy needs, reported lower quality of life determinants compared to elderly individuals who had an interest in a dietary pattern according to their needs24. Our study is consistent with these results, where it can be observed that the combined and nutrition groups presented significant results compared to the combined group, which did not receive nutritional guidance.
The present study also observed that the nutritionally instructed groups also improved their score in relation to the physical activity level questionnaire. It was evidenced that the combined and nutrition group, after intervention, increased the amount of minutes per week in which they performed light activities. The literature has highlighted that lifestyle, considering dietary patterns, are behavioral factors that can directly reflect on the individual's level of physical activity25. A 2016 study with Brazilian adults and elderly individuals presented a greater tendency of chances for the population that was instructed in their diet and/or concerned about their nutritional intake to engage in physical activities compared to people who did not receive any guidance or were not concerned about their diet26. Therefore, the study concludes the importance of encouraging public policies for good nutrition and physical activity, since the literature has enough studies to affirm that these factors are interrelated, as this study can also indicate.
Regarding combined and multicomponent training interventions, they are well described in the literature as beneficial and effective for the health of the aging population. In the study by Rodrigues et al. (2021), which compared the two intervention models for 14 weeks in physically active elderly women, it was found that combined training was better than component training only in terms of cardiorespiratory capacity, and that all other benefits of functionality and capacity were observed in both groups3. Our study was not able to identify a significant improvement when comparing one training model with the other.
Regarding food intake, we can highlight that the two nutritionally instructed groups: combined and nutrition, and multicomponent and nutrition, had higher mean protein intake in grams after the intervention compared to before and compared to the other groups. This result becomes more significant when we consider that, in the age range of the participants, protein intake associated with regular physical exercise is a measure against sarcopenia, which can lead to undesirable clinical outcomes such as increased risk of falls and in some cases even hospitalization27.
However, it has been evidenced that the association of adequate protein intake and regular physical exercise is not only important for the prevention of sarcopenia. Rizzoli et al. (2017) showed the beneficial effect of this association in the prevention and delay of diseases as well as in increasing strength, muscle mass, and resistance in older individuals28. Similarly, Torres et al. (2017) demonstrated that during a 16-week nutritional intervention, the intake of protein in elderly women was significantly improved through resistance exercise, resulting in an improvement in quality of life and health parameters29.
Regarding calcium intake, it was observed that the multicomponent nutritionally oriented group had higher calcium intake compared to the other groups in the post-intervention period. This is another significant result considering that the bone density of this population depends on exercise routine and nutrient intake, such as calcium. However, for lipid profile and fasting glucose, as well as metabolic results, no significant differences were observed in any of the groups in this study.
Motallebi et al. (2018) demonstrated a positive effect of exercise associated with nutrition in physically inactive elderly women during 24 weeks of training, such as a decrease in total cholesterol and an increase in HDL30. Therefore, further studies with physically active women from the sample, as in this study, should be carried out for greater clarification, as well as interventions of shorter duration.
Regarding the limitations of the study, it should be noted that it was not possible to biologically confirm whether the studied population effectively maintained the recommended dietary pattern during the 14 weeks. No physiological variable was used as a marker of adherence to the dietary prescription, such as glycemic control through dextrose.
This study presented limitations that should be considered, such as the small number of participants per group, the reduced total number of participants, the wide age range of the participants, and the short intervention period.