Measurement of body composition in response to a short period of overfeeding

Greater energy surplus promotes body protein accretion in healthy young men: A randomized clinical trial

BACKGROUND & AIMS

Caloric overfeeding combined with adequate protein intake increases not only body fat mass but also fat-free mass. However, it remains unclear whether the increase in fat-free mass due to overfeeding is associated with an increase in total body protein mass. We evaluated the hypothesis that overfeeding would promote an increase in total body protein mass.

METHODS

In our randomized controlled trial, 23 healthy young men were fed a diet equivalent to their energy requirements with a +10 % energy surplus from protein alone or a +40 % energy surplus (+10 % from protein, +30 % from carbohydrate) for 6 weeks. We estimated total body protein mass by a four-compartment model using dual-energy X-ray absorptiometry, deuterium dilution, and hydrostatic underwater weighing.

RESULTS

The 40 % energy surplus over 6 weeks significantly increased body protein mass compared to baseline by 3.7 % (0.44 kg; 95 % confidence interval [CI], 0.21-0.67 kg; P = 0.003); however, the 10 % energy surplus did not result in a significant change (0.00 kg; 95 % CI, -0.38-0.39 kg; P = 0.980). A significant interaction between intervention duration (time) and energy surplus (group) was observed for total body protein mass (P = 0.035, linear mixed-effects model), with a trend toward a significant difference in total body protein mass gain between groups (P = 0.059, Wilcoxon rank sum test). The increase in body protein mass due to the energy surplus was correlated with an increase in fat mass (r = 0.820, p = 0.002).

CONCLUSIONS

A higher energy intake was found to promote an increase in body protein mass in healthy men consuming excess protein, suggesting the importance of energy surplus in body protein accumulation. This effect of energy surplus may be related to factors such as increased body fat mass and the associated secretion of adipokines.

TRIAL REGISTRATION

The trial was registered with the University Hospital Medical Information Network Clinical Trial Registry as UMIN000034158.

Effect of 1-Week Weight Loss While Maintaining Total Body Water on Jump Performance

Jumping performance is influenced by body composition and excess fat mass impairs performance. Maintaining optimal fat mass and fat-free mass (FFM) is crucial for enhancing jump height. However, there is limited evidence on short-term weight loss programs that reduce fat mass without water restriction and their effects on muscle function and jumping performance. This study aimed to clarify the effects of a 1-week weight loss program on jumping height and muscle function of volleyball players. The weight loss group engaged in two 40 min slow-paced jogging sessions in addition to their daily training routine. Energy intake was restricted without limitations on water intake. Total body water and body composition using the deuterium dilution method, muscle strength, and jump height before and after 1 week were evaluated for those in the weight loss and control groups. Body mass was significantly reduced in the weight loss group (-2.7 ± 1.3%, p < 0.05) with a significant reduction in fat mass (-17.7 ± 10.7%, p < 0.05). Meanwhile, there were no significant changes in total body water or FFM. Muscle strength and power tests indicated no significant differences between the groups; no notable differences were observed in handgrip strength or knee extension torque. The height of a single vertical and continuous jump remained consistent pre- and postintervention in the control group. In the weight loss group, although the height of a single vertical jump exhibited a slight decline postintervention, the height of a continuous jump displayed no significant changes. The short-term weight loss program significantly reduced fat mass without compromising muscle function, which is crucial for sports performance. These findings may benefit other athletes who require fat mass reduction while maintaining muscle function and help create new programs during specific training phases.

Comparison of Bioelectrical Impedance Indices for Skeletal Muscle Mass and Intracellular Water Measurements of Physically Active Young Men and Athletes

BACKGROUND

Bioelectrical impedance analysis (BIA) is a minimally invasive, safe, easy, and quick technology used to determine body composition.

OBJECTIVES

We compared the relationship among impedance indices obtained using single-frequency BIA, multi-frequency BIA, bioelectrical impedance spectroscopy (BIS), and skeletal muscle mass (SMM) of physically active young men and athletes using the creatine (methyl-d3) dilution method. We also compared the SMM and intracellular water (ICW) of athletes and active young men measured using a reference stable isotope dilution and BIS method, respectively.

METHODS

We analyzed data from 28 men (mean age, 20 ± 2 y) who exercised regularly. Single-frequency BIA at 5 kHz and 50 kHz (R5 and R50), multi-frequency BIA (R250-5), and BIS (RICW) methods of determining the SMM were compared. The deuterium and sodium bromide dilution methods of obtaining the total body water, ICW, and extracellular water measurements were also used, and the results were compared to those acquired using bioimpedance methods.

RESULTS

The correlation coefficients between SMM and L2/R5, L2/R50, L2/R250-5, and L2/RICW were 0.738, 0.762, 0.790, and 0.790, respectively (P < 0.01). The correlation coefficients between ICW and L2/R5, L2/R50, L2/R250-5, and L2/RICW were 0.660, 0.687, 0.758, and 0.730, respectively (P < 0.001). However, the correlation coefficients of L2/R50, L2/R250-5, and L2/RICW for SMM and ICW were not significantly different.

CONCLUSIONS

Our findings suggest that single-frequency BIA at L2/R50, multi-frequency BIA, and BIS are valid for assessing the SMM of athletes and active young men. Additionally, we confirmed that the SMM and ICW were correlated with single-frequency BIA, multi-frequency BIA, and BIS. Bioimpedance technologies may be dependable and practical means for assessing SMM and hydration compartment status of active young adult males; however, cross-validation is needed.

Downsizing food: a systematic review and meta-analysis examining the effect of reducing served food portion sizes on daily energy intake and body weight

Portion sizes of many foods have increased over time. However, the size of effect that reducing food portion sizes has on daily energy intake and body weight is less clear. We used a systematic review methodology to identify eligible articles that used an experimental design to manipulate portion size served to human participants and measured energy intake for a minimum of 1 d. Searches were conducted in September 2020 and again in October 2021. Fourteen eligible studies contributing eighty-five effects were included in the primary meta-analysis. There was a moderate-to-large reduction in daily energy intake when comparing smaller v. larger portions (Standardised Mean Difference (SMD) = -0·709 (95 % CI: -0·956, -0·461), approximately 235 kcal (983·24 kJ)). Larger reductions to portion size resulted in larger decreases in daily energy intake. There was evidence of a curvilinear relationship between portion size and daily energy intake; reductions to daily energy intake were markedly smaller when reducing portion size from very large portions. In a subset of studies that measured body weight (four studies contributing five comparisons), being served smaller v. larger portions was associated with less weight gain (0·58 kg). Reducing food portion sizes may be an effective population-level strategy to prevent weight gain.

Association between Intra- and Extra-Cellular Water Ratio Imbalance and Natriuretic Peptides in Patients Undergoing Hemodialysis

Natriuretic peptides are associated with malnutrition and volume overload. Over-hydration cannot simply be explained by excess extracellular water in patients undergoing hemodialysis. We assessed the relationship between the extracellular and intracellular water (ECW/ICW) ratio, N-terminal pro-B-type natriuretic peptide (NT-proBNP), human atrial natriuretic peptide (hANP), and echocardiographic findings. Body composition was examined by segmental multi-frequency bioelectrical impedance analysis in 368 patients undergoing maintenance dialysis (261 men and 107 women; mean age, 65 ± 12 years). Patients with higher ECW/ICW ratio quartiles tended to be older, were on dialysis longer, and had higher post-dialysis blood pressure and lower body mass index, ultrafiltration volume, serum albumin, blood urea nitrogen, and creatinine levels (p < 0.05). The ECW/ICW ratio significantly increased with decreasing ICW, but not with ECW. Patients with a higher ECW/ICW ratio and lower percent fat had significantly higher natriuretic peptide levels. After adjusting for covariates, the ECW/ICW ratio remained an independent associated factor for natriuretic peptides (β = 0.34, p < 0.001 for NT-proBNP and β = 0.40, p < 0.001 for hANP) and the left ventricular mass index (β = 0.20, p = 0.002). The ICW-ECW volume imbalance regulated by decreased cell mass may explain the reserve capacity for fluid accumulation in patients undergoing hemodialysis.

Validity of Bioimpedance Spectroscopy in the Assessment of Total Body Water and Body Composition in Wrestlers and Untrained Subjects

Bioimpedance spectroscopy (BIS) is an easy tool to assess hydration status and body composition. However, its validity in athletes remains controversial. We investigated the validity of BIS on total body water (TBW) and body composition estimation in Japanese wrestlers and untrained subjects. TBW of 49 young Japanese male subjects (31 untrained, 18 wrestlers) were assessed using the deuterium dilution method (DDM) and BIS. De Lorenzo’s and Moissl’s equations were employed in BIS for TBW estimation. To evaluate body composition, Siri’s 3-compartment model and published TBW/fat-free mass (FFM) ratio were applied in DDM and BIS, respectively. In untrained subjects, DDM and BIS with de Lorenzo’s equation showed consistent TBW estimates, whereas BIS with Moissl’s equation overestimated TBW (p < 0.001 vs. DDM). DDM and BIS with de Lorenzo’s equation estimated FFM and percent of fat mass consistently, whereas BIS with Moissl’s equation over-estimated and under-estimated them (p < 0.001 vs. DDM). In wrestlers, BIS with de Lorenzo’s and Moissl’s equations assessed TBW similarly with DDM. However, the Bland–Altman analysis revealed a proportional bias for TBW in BIS with de Lorenzo’s equation (r = 0.735, p < 0.001). Body composition assessed with BIS using both equations and DDM were not different. In conclusion, BIS with de Lorenzo’s equation accurately estimates the TBW and body composition in untrained subjects, whereas BIS with Moissl’s equation is more valid in wrestlers. Our results demonstrated the usefulness of BIS for assessing TBW and body composition in Japanese male wrestlers.

The biology of human overfeeding: A systematic review

This systematic review has examined more than 300 original papers dealing with the biology of overfeeding. Studies have varied from 1 day to 6 months. Overfeeding produced weight gain in adolescents, adult men and women and in older men. In longer term studies, there was a clear and highly significant relationship between energy ingested and weight gain and fat storage with limited individual differences. There is some evidence for a contribution of a genetic component to this response variability. The response to overfeeding was affected by the baseline state of the groups being compared: those with insulin resistance versus insulin sensitivity; those prone to obesity versus those resistant to obesity; and those with metabolically abnormal obesity versus those with metabolically normal obesity. Dietary components, such as total fat, polyunsaturated fat and carbohydrate influenced the patterns of adipose tissue distribution as did the history of low or normal birth weight. Overfeeding affected the endocrine system with increased circulating concentrations of insulin and triiodothyronine frequently present. Growth hormone, in contrast, was rapidly suppressed. Changes in plasma lipids were influenced by diet, exercise and the magnitude of weight gain. Adipose tissue and skeletal muscle morphology and metabolism are substantially altered by chronic overfeeding.

An in vitro model for hypertrophic adipocytes: Time-dependent adipocyte proteome and secretome changes under high glucose and high insulin conditions

Obesity is the consequence of a positive energy balance and characterized by enlargement of the adipose tissue, which in part is due to hyperplasia and hypertrophy of the adipocytes. Not much is known about the transition of normal mature adipocytes to the hypertrophic state, which in vivo is very hard to study. Here, we have maintained mature human SGBS cells as a surrogate for adipocytes, changes of morphological and molecular metabolism of the adipocytes were monitored over the first 4 days and the last 4 days. In total, 393 cellular proteins and 246 secreted proteins were identified for further analysis. During the first 4 days of high glucose and insulin, the adipocytes seemed to prefer pyruvate as energy source, whereas beta‐oxidation was down‐regulated supporting lipid loading. Over time, lipid droplet fusion instead of lipid uptake became relatively important for growth of lipid droplets during the last 4 days. Moreover, ECM production shifted towards ECM turnover by the up‐regulation of proteases over eight days. The present in vitro system provides insight into the metabolic changes of adipocytes under conditions of high glucose and insulin, which may help to understand the process of in vivo adipocyte hypertrophy during the development of obesity.

Evaluation of fat-free mass hydration in athletes and non-athletes

PURPOSE

To evaluate the hydration of fat-free mass (FFM) in athletes and non-athletes.

METHODS

We analyzed the data of 128 healthy young adults (athletes: 61 men, 36 women; non-athletes: 19 men, 12 women) using the two-component (2C), 3C and 4C models. Under-water weighing or air-displacement plethysmography and deuterium dilution methods were used for estimating body density and total body water, respectively. The bone mineral content (BMC) was determined using whole-body scans by dual-energy X-ray absorptiometry.

RESULTS

There was no significant difference in FFM hydration between the athletes (men, 72.3 ± 1.3%; women, 71.8 ± 1.3%) and non-athletes (men, 72.1 ± 1.2%; women, 72.2% ± 1.0%) in the 3C model. The total mean FFM hydration (72.1% ± 1.3%) was similar to the corresponding value in the literature (~ 73%). The estimation error of the percentage fat by the 2C vs the 4C model was significantly and highly correlated with hydration (r = 0.96), BMC (r = - 0.70), and total body protein (r = - 0.86) in the 4C model FFM.

CONCLUSION

Although FFM hydration was similar in athletes and non-athletes, it would be underestimated or overestimated when the 2C model is used for evaluation, and the biological FFM hydration value deviates from the 73% value inter-individually. Despite that this inter-individual variation in FFM hydration is low in terms of between-individual standard deviation (1.3%), the BMC and total body protein differ greatly in athletes, and when it affects FFM hydration, it may also affect the percentage fat measurement in the 2C model. Thus, FFM hydration would not be affected by FFM, percent body fat, or the athletic status.

Is an Energy Surplus Required to Maximize Skeletal Muscle Hypertrophy Associated With Resistance Training

Resistance training is commonly prescribed to enhance strength/power qualities and is achieved via improved neuromuscular recruitment, fiber type transition, and/ or skeletal muscle hypertrophy. The rate and amount of muscle hypertrophy associated with resistance training is influenced by a wide array of variables including the training program, plus training experience, gender, genetic predisposition, and nutritional status of the individual. Various dietary interventions have been proposed to influence muscle hypertrophy, including manipulation of protein intake, specific supplement prescription, and creation of an energy surplus. While recent research has provided significant insight into optimization of dietary protein intake and application of evidence based supplements, the specific energy surplus required to facilitate muscle hypertrophy is unknown. However, there is clear evidence of an anabolic stimulus possible from an energy surplus, even independent of resistance training. Common textbook recommendations are often based solely on the assumed energy stored within the tissue being assimilated. Unfortunately, such guidance likely fails to account for other energetically expensive processes associated with muscle hypertrophy, the acute metabolic adjustments that occur in response to an energy surplus, or individual nuances like training experience and energy status of the individual. Given the ambiguous nature of these calculations, it is not surprising to see broad ranging guidance on energy needs. These estimates have never been validated in a resistance training population to confirm the "sweet spot" for an energy surplus that facilitates optimal rates of muscle gain relative to fat mass. This review not only addresses the influence of an energy surplus on resistance training outcomes, but also explores other pertinent issues, including "how much should energy intake be increased," "where should this extra energy come from," and "when should this extra energy be consumed." Several gaps in the literature are identified, with the hope this will stimulate further research interest in this area. Having a broader appreciation of these issues will assist practitioners in the establishment of dietary strategies that facilitate resistance training adaptations while also addressing other important nutrition related issues such as optimization of fuelling and recovery goals. Practical issues like the management of satiety when attempting to increase energy intake are also addressed.

Effect of the Health Tourism weight loss programme on body composition and health outcomes in healthy and excess-weight adults

Excess weight loss while minimising fat-free mass (FFM) loss is important for health. Travel is a particular period at risk for weight gain and for which the effects of a short-term intensive weight loss programme have not been studied. Therefore, we studied the effect of a novel, 1-week supervised health travel programme combining high volume, low-to-moderate intensity exercise and energy intake restriction on weight, body composition and health outcomes in adults. Weight was also monitored for 12 weeks after the programme. In all, thirty-six subjects (nineteen men, seventeen women) consisting of sixteen excess-weight (BMI: 27·1 (sd 1·7) kg/m2) and twenty healthy-weight (BMI: 22·3 (sd 1·8) kg/m2) individuals participated. Subjects performed 1 h of slow-paced intermittent jogging three times per d and other leisure activities, whereas consuming only provided foods without water restriction. Body mass significantly decreased from pre- to post-intervention in excess-weight and healthy-weight individuals (-3·5 (sd 1·5) and -3·5 (sd 1·3) %, respectively; P<0·001 for both), and losses were maintained at 12 weeks post-intervention in both groups (-6·3 (sd 3·8) and -1·7 (sd 4·0) %, respectively; P<0·01 for both). Fat mass also significantly decreased in both groups (excess weight: -9·2 (sd 4·6) %: healthy weight: -13·4 (sd 9·0) %; P<0·01 for both), whereas FFM was maintained. Similar improvements were observed for blood biochemistry and pressure in both groups. This short-term weight loss intervention yielded favourable outcomes in both excess- and healthy-weight adults, particularly a 3·5 % weight loss with no significant change to FFM. In addition, participants maintained weight loss for at least 12 weeks. Of multiple programme choices, the Health Tourism weight loss programme's results indicate that it is a viable option.