Can the body mass index influence the skin temperature of adolescents assessed by infrared thermography?

Infrared thermography (IRT) is a technology that has been used as an auxiliary tool in the diagnostic process of several diseases and in sports monitoring to prevent injuries. However, the evaluation of a thermogram can be influenced by several factors that need to be understood and controlled to avoid a misinterpretation of the thermogram and, consequently, an inappropriate clinical action. Among the possible factors that can affect IRT are anthropometric factors, especially those related to body composition. Based on these, our objective was to verify the influence of Body Mass Index (BMI) on skin temperature (Tsk) in male adolescents. One hundred male adolescents (age: 16.83 ±â€¯1.08 years; body mass: 66.51 ±â€¯13.35 kg; height: 1.75 ±â€¯7.04 m and BMI: 21.57 ±â€¯4.06 kg/m2) were evaluated and divided into three groups, based on the World Health Organization (WHO) proposed classification ranges: underweight (n = 33), normal weight (n = 34) and overweight/obesity (n = 34). Thermograms were obtained using the FLIR T420 thermal imager after a period of acclimatization of the subjects in a controlled environment (temperature: 21.3 ±â€¯0.7 °C and humidity: 55.3 ±â€¯2.2%); they were evaluated using the ThermoHuman® software, integrating the original regions of interest (ROI) into seven larger ROIs. The results showed that underweight individuals had higher Tsk values than normal weight and overweight/obese individuals for all evaluated ROIs, and overweight/obese individuals had lower Tsk values than normal weight individuals for most evaluated ROIs, except for arms region. BMI showed a correlation of -0.68 and -0.64 for the anterior and posterior regions of the trunk, respectively. Thermal normality tables were proposed for various ROIs according to BMI classification. Our study demonstrated that BMI can affect the Tsk values assessed by IRT and needs to be considered to interpret the thermograms.

Acute effect of auxotonic and isometric contraction evaluated by infrared thermography in handball players.

The Infrared Thermography (IRT) is being used in the field of sport as a means of quantifying the effects of workload. The aims of this study were (i) to determine the variations in skin temperature (Tsk) of the lower limbs after an effort of auxotonic and isometric squat contractions using infrared thermography and (ii) to study jumping performance variations in handball players after those two different contraction types. A total of 15 national level handball players voluntarily participated in the study (age: 23.20 ± 5.23 years). Two types of protocols - isometric and auxotonic - were performed on different days, having previously calculated the maximal isometric squat strength and auxotonic 1RM. During the data collection, participants performed a specific standardized warm-up and then randomly performed 4x10 repetitions of auxotonic squat to 90° of knee flexion at 70% of 1RM and 4x10 s of isometric squat effort at 90° of knee flexion, at 70% of maximal isometric squat strength (both with a passive recovery of 90 s seated). Rate of perceived exertion (RPE) and countermovement jumping performance (CMJ) were measured before and immediately after efforts. Additionally, infrared thermography data from twelve regions of interest of the lower limbs were registered before, immediately after and 15 min after finishing the effort. The main results indicated no significant differences for RPE (p = 0.486), CMJ vertical height (VH; p = 0.344) and Tsk (p > 0.05) in any of the regions of interest after protocols. Significant differences (p < 0.05) were found for the time of data collection on Tsk with similar pre- and post-15 min values. In conclusion, Tsk decreased after both isometric and auxotonic effort at 70% of the maximal performance and recovered baseline values within 15 min of completion. Both efforts produced similar effects on skin temperature and did not affect jumping performance after exercise.

Equations based on anthropometric measurements for adipose tissue, body fat, or body density prediction in children and adolescents: a scoping review.

PURPOSE: Assessing the body composition of children and adolescents is important to monitor their health status. Anthropometric measurements are feasible and less-expensive than other techniques for body composition assessment. This study aimed to systematically map anthropometric equations to predict adipose tissue, body fat, or density in children and adolescents, and to analyze methodological aspects of the development of anthropometric equations using skinfolds. METHODS: A scoping review was carried out following the PRISMA-ScR criteria. The search was carried out in eight databases. The methodological structure protocol of this scoping review was retrospectively registered in the Open Science Framework ( https://osf.io/35uhc/ ). RESULTS: We included 78 reports and 593 anthropometric equations. The samples consisted of healthy individuals, people with different diseases or disabilities, and athletes from different sports. Dual-energy X-ray absorptiometry (DXA) was the reference method most commonly used in developing equations. Triceps and subscapular skinfolds were the anthropometric measurements most frequently used as predictors in the equations. Age, stage of sexual maturation, and peak height velocity were used as complementary variables in the equations. CONCLUSION: Our scoping review identified equations proposed for children and adolescents with a great diversity of characteristics. In many of the reports, important methodological aspects were not addressed, a factor that may be associated with equation bias. LEVEL IV: Evidence obtained from multiple time series analysis such as case studies. (NB: dramatic results in uncontrolled trials might also be regarded as this type of evidence).

Ischemic Preconditioning and Muscle Force Capabilities.

ABSTRACT: Valenzuela, PL, Martín-Candilejo, R, Sánchez-Martínez, G, Bouzas Marins, JC, de la Villa, P, and Sillero-Quintana, M. Ischemic preconditioning and muscle force capabilities. J Strength Cond Res 35(8): 2187-2192, 2021-This study analyzed the effects of ischemic preconditioning (IPC) on muscle force capabilities. Sixteen male subjects participated in this randomized, crossover, sham-controlled study. They were assigned to either IPC (3 × 5 minutes at 220 mm Hg in both arms with 5-minute rests) or a sham intervention (SHAM) (occlusion pressure set at 10 mm Hg). Forty minutes later, their force capabilities on the bench press exercise were assessed (load-velocity relationship with light, moderate, and heavy loads [30, 50, and 70% body mass, respectively]; 1 repetition maximum [1RM]; and number of repetitions to failure in 3 sets with 60% RM). The skin temperature (Tsk) of the pectoral and biceps muscles was analyzed as a secondary endpoint by means of infrared thermography. A significant decrease in the Tsk of the pectoral and biceps muscles was observed after the intervention (p < 0.01) and before the warm-up (p < 0.05) in IPC, but not in SHAM. However, exercise resulted in a similar Tsk increase in the pectoral muscles in both conditions (p > 0.05). No significant differences (p > 0.05 for all) were observed between conditions in the mean velocity attained with light (1.11 ± 0.11 and 1.09 ± 0.14 m·s-1, respectively), moderate (0.83 ± 0.14 and 0.83 ± 0.16 m·s-1), nor heavy loads (0.56 ± 0.17 and 0.54 ± 0.16 m·s-1), in 1RM (75.0 ± 18.9 and 73.1 ± 15.0 kg for IPC and SHAM, respectively; p = 0.181), nor in the number of repetitions performed (52 ± 13 and 54 ± 16 repetitions, p = 0.492). In summary, IPC decreased Tsk locally (biceps) and remotely (pectoral). However, it did not alter muscle force capabilities nor the Tsk response to exercise.

Lactate Concentration Is Related to Skin Temperature Variation After a Specific Incremental Judo Test.

ABSTRACT: Gomes Moreira, D, José Brito, C, de Almeida Ferreira, JJ, Bouzas Marins, JC, López Díaz de Durana, A, Couceiro Canalejo, J, Butragueño Revenga, J, and Sillero-Quintana, M. Lactate concentration is related to skin temperature variation after a specific incremental judo test. J Strength Cond Res 35(8): 2213-2221, 2021-This study aimed to analyze the skin temperature (tsk) response in judokas after a specific incremental test and to determine whether anthropometric and physiological measures can be explained by the variation in mean tsk. A total of 23 male judo athletes (age: 20.1 ± 4.7 years; height: 173.1 ± 8.1 cm; and body mass: 71.7 ± 8.1 kg) performed a specific incremental judo test. Skin temperature evaluations were collected in 26 regions of interest (ROIs), and the mean tsk was calculated using an equation including 10 of them. The time points before the test (pre-test), immediately after (0 minutes), and after 5, 10, and 15 minutes of the test were established to measure the tsk, mean tsk, auricular temperature (tau), and blood lactate (LAC). The athletes completed a mean of 7.0 ± 1.0 stages of the test, 95% confidence interval (CI; 6.2-7.1). The V̇o2peak achieved was 48.7 ± 5.3 ml·kg-1·min-1, 95% CI (46.4-51.0). Compared with pre-test values, only the forehead significantly decreased 5 minutes after the test (p < 0.05). The posterior right arm and posterior left arm remained increased 10 minutes after the test (p < 0.05). After 15 minutes, 19 of the 26 ROIs analyzed were significantly decreased (p < 0.05). Among all tested models of linear regression, only 2 were significant, the difference of tsk 5 minutes compared with pre-test (F1, 21 = 16.49, p = 0.001) and the difference of tsk 10 minutes compared with pre-test, to predict LAC concentration at the end of the test (F1, 21 = 9.30, p = 0.006). We concluded that 5 minutes after the test, the judokas present a higher tau and a higher tsk in 7 ROIs, and the tsk decreases 15 minutes after the test in 19 of the considered ROIs. The variation of mean tsk 5 and 10 minutes after the test compared with pre-test values is associated with blood LAC at the end of the test.

Immune Response Related With Skin Thermal Pattern in Judokas: A New Application for Infrared Thermography?

Brito, CJ, Moreira, DG, Ferreira, JJ, Díaz-de-Durana, AL, Miarka, B, Bouzas Marins, JC, and Sillero-Quintana, M. Immune response related with skin thermal pattern in judokas: A new application for infrared thermography? J Strength Cond Res 34(10): 2886-2894, 2020-This study investigated the association between body skin temperature (BST) and immune response after judo training, and compared the immune responses considering 2 post-training skin thermal pattern ("spots"-SPT and "localized"-LOC). For this, we evaluated 32 (25-male) black-belt judokas from the Spanish Junior National Team (18.0 ± 3.5 years, 72.4 ± 18.4 kg, and 17.1 ± 7.5% body fat). White blood cell and BST measurements were performed at pre-training, immediately, 1, and 24-hour post-training. Body skin temperature (° C) was estimated by skin temperature from 4 regions of interest (chest, upper arm, thigh, and calf). The main results indicated that 13 judokas were classified as SPT and 19 as LOC. In comparison with LOC, SPT had a significantly lower BST post-training (SPT = 33.0 ± 0.4 vs. LOC = 33.6 ± 0.8° C; p = 0.016), lower blood concentration of leukocytes (SPT = 7.9 ± 1.9 vs. LOC = 8.9 ± 1.9 cells × 10 per mm; p ≤ 0.001), and neutrophils (SPT = 5.5 ± 1.7 vs. LOC = 6.1 ± 2.2 cells × 10 per mm; p ≤ 0.001). In conclusion, the BST and immune response after judo training seem to be not associated. However, when the skin thermal pattern is considered, the SPT skin thermal pattern presented a lower post-training BST, blood leukocytes, and neutrophils in comparison with the LOC group. These results show a possible relationship between skin thermal pattern and immune responses for the first time; however, further studies are needed to confirm the evidence presented here.

Infrared Thermography Protocol on Reducing the Incidence of Soccer Injuries.

CONTEXT: Infrared thermography has been used to detect skeletal muscle overload and fatigue in athletes, but its use in injury prevention in professional soccer has not been studied to date. OBJECTIVES: To establish a novel injury prevention program based on infrared thermography and to determine its influence on the injury incidence in professional soccer players in the preseason. DESIGN: A cross-sectional, prospective study design was used to compare a conventional injury prevention program (CPP) applied over the first preseason and an infrared thermography injury prevention program (IRTPP) carried out in the following preseason. SETTING: Soccer training ground. PARTICIPANTS: Twenty-four players belonging to a first division soccer team from Spain. MAIN OUTCOME MEASURES: Injury incidences of each player were recorded according to the Orchard Sports Injury Classification System (version 10.0) convention to determine the injury classification, location, and type. RESULTS: The incidence of injuries decreased from 15 injuries in the CPP preseason (0.63 [0.77] injuries per player) to 6 injuries in the second preseason when the IRTPP was applied (0.25 [0.53] injuries per player). The days of absence due to injuries also decreased from the CPP preseason (156 d, 10.4 [11.0] d per injury) to the IRTPP preseason (14 d, 2.3 [2.8] d per injury). The injury severity also decreased from the first preseason to the second preseason, and fewer musculoskeletal injuries in the thigh, hip, and groin were reported. CONCLUSIONS: The implementation of an IRTPP can reduce the presence of injuries by identifying players potentially at risk and as a result, reducing the injury severity and days lost as a consequence.

Daily rhythm of skin temperature of women evaluated by infrared thermal imaging.

It is well known that skin temperature varies due to circadian rhythm. Although there is information available for men, little is known about women's circadian rhythm in the analysis of skin temperature (Tsk) using infrared thermography. The objective of this study is to identify Tsk variations on different body regions in women through infrared thermography during the day. The sample consisted of 20 female (mean age of 20.5 ± 1.3 years, body weight of 62.2 ± 9.2kg and height of 165.0 ± 4.7cm). Oneway ANOVA for repeated measures, and Cosinor analysis was used to determine the MESOR, amplitude and acrophase of Tsk. The regions of the forearm, upper arm and anterior and posterior legs in the lower limbs, as well as the chest and scapulae in the upper limbs showed higher variability throughout the day. In general, distal regions had lower values compared with the central regions, and the pectoral region had the lowest standard deviation values. Tsk of the analyzed regions at different times show significant differences between periods of the day in young active women, showing the minimum absolute values for both Tsk in the early morning. These results highlight the need to consider the time of day when analyzing women's skin temperature. Future studies should report the time of day when the images were collected, as well as consider the circadian rhythm when making comparisons.

Thermographic imaging in sports and exercise medicine: A Delphi study and consensus statement on the measurement of human skin temperature.

The importance of using infrared thermography (IRT) to assess skin temperature (tsk) is increasing in clinical settings. Recently, its use has been increasing in sports and exercise medicine; however, no consensus guideline exists to address the methods for collecting data in such situations. The aim of this study was to develop a checklist for the collection of tsk using IRT in sports and exercise medicine. We carried out a Delphi study to set a checklist based on consensus agreement from leading experts in the field. Panelists (n = 24) representing the areas of sport science (n = 8; 33%), physiology (n = 7; 29%), physiotherapy (n = 3; 13%) and medicine (n = 6; 25%), from 13 different countries completed the Delphi process. An initial list of 16 points was proposed which was rated and commented on by panelists in three rounds of anonymous surveys following a standard Delphi procedure. The panel reached consensus on 15 items which encompassed the participants' demographic information, camera/room or environment setup and recording/analysis of tsk using IRT. The results of the Delphi produced the checklist entitled "Thermographic Imaging in Sports and Exercise Medicine (TISEM)" which is a proposal to standardize the collection and analysis of tsk data using IRT. It is intended that the TISEM can also be applied to evaluate bias in thermographic studies and to guide practitioners in the use of this technique.

Validity of inner canthus temperature recorded by infrared thermography as a non-invasive surrogate measure for core temperature at rest, during exercise and recovery.

Research into obtaining a fast, valid, reliable and non-invasive measure of core temperature is of interest in many disciplinary fields. Occupational and sports medicine research has attempted to determine a non-invasive proxy for core temperature particularly when access to participants is limited and thermal safety is of a concern due to protective encapsulating clothing, hot ambient environments and/or high endogenous heat production during athletic competition. This investigation aimed to determine the validity of inner canthus of the eye temperature (TEC) as an alternate non-invasive measure of intestinal core temperature (TC) during rest, exercise and post-exercise conditions. Twelve physically active males rested for 30min prior to exercise, performed 60min of aerobic exercise at 60% V̇O2max and passively recovered a further 60min post-exercise. TEC and TC were measured at 5min intervals during each condition. Mean differences between TEC and TC were 0.61°C during pre-exercise, -1.78°C during exercise and -1.00°C during post-exercise. The reliability between the methods was low in the pre-exercise (ICC=0.49 [-0.09 to 0.82]), exercise (ICC=-0.14 [-0.65 to 0.44]) and post-exercise (ICC=-0.25 [-0.70 to 0.35]) conditions. In conclusion, poor agreement was observed between the TEC values measured through IRT and TC measured through a gastrointestinal telemetry pill. Therefore, TEC is not a valid substitute measurement to gastrointestinal telemetry pill in sports and exercise science settings.

Epidemiology of injuries in First Division Spanish football.

The aim was to examine the injuries sustained by Spanish football players in the First Division and to compare injury-related variables in the context of both competition and training. The injury data were prospectively collected from 16 teams (427 players) using a specific web-based survey during the 2008/2009 season. A total of 1293 injuries were identified (145 were recurring injuries). The overall injury incidence was 5.65 injuries per 1000 h of exposure. Injuries were much more common during competition than during training (43.53 vs. 3.55 injuries per 1000 h of exposure, P < 0.05). Most of the injuries (89.6%) involved the lower extremities, and overuse (65.7%) was the main cause. Muscle and tendon injuries were the most common types of injury (53.8%) among the players. The incidence of training injuries was greater during the pre-season and tended to decrease throughout the season, while the incidence of competition injuries increased throughout the season (all P < 0.05). In conclusion, the results of this study suggest the need for injury prevention protocols in the First Division of the Spanish Football League to reduce the number of overuse injuries in the muscles and tendons in the lower extremities. In addition, special attention should be paid during the pre-season and the competitive phase II (the last four months of the season) in order to prevent training and competition injuries, respectively.

Thermal body patterns for healthy Brazilian adults (male and female).

The aim of this study was to establish the skin temperature (Tsk) thermal profile for the Brazilian population and to compare the differences between female and male Brazilian adults. A total of 117 female and 103 male were examined with a thermographic camera. The Tsk of 24 body regions of interest (ROI) were recorded and analyzed. Male Tsk results were compared to female and 10 ROI were evaluated with respect to the opposite side of the body (right vs. left) to identify the existence of significant contralateral Tsk differences (ΔTsk). When compared right to left, the largest contralateral ΔTsk was 0.3°C. The female vs. male analysis yielded significant differences (p<0.05) in 13 of the 24 ROI. Thigh regions, both ventral and dorsal, had the highest ΔTsk by sex (≈1.0°C). Tsk percentile below P5 or P10 and over P90 or P95 may be used to characterize hypothermia and hyperthermia states, respectively. Thermal patterns and Tsk tables were established for Brazilian adult men and women for each ROI. There is a low Tsk variation between sides of the body and gender differences were only significant for some ROIs.

Effect of Whole-, Upper-, and Lower-Body High-Intensity Rowing Exercise on Skin Temperature Measured by Thermography.

Purpose: Despite the growing works analyzing exercise-induced thermoregulatory adjustments through thermography, the skin temperature (Tsk) response of the same muscle groups underwent to different exercise demands has not been investigated. This study analyzed the behavior of Tsk of the same muscle groups when exercised with different demands in rowing. Methods: Eighteen men underwent three performance tests on a rowing ergometer: whole-body 2,000 m test (RTWB), upper-body (RTUB), and lower-body (RTLB) tests. In each condition, thermograms were recorded before (pre), immediately after test (post), and at 10 (REC10), 20 (REC20), and 30 (REC30) minutes post-exercise recovery. Tsk was measured at the pectoral (control body region), upper back, quadriceps, brachial biceps, and forearm. Results: Pectoral-Tsk reduced comparably in response to all testing conditions (p < .05). Upper back-Tsk decreased post (p < .001) and returned to baseline in the RTUB (REC10, p = 1.0) and RTWB (REC30, p = .128), while remained reduced in the RTLB (p < .001). Quadriceps-Tsk reduced post (p < .05) and returned to baseline in the RTWB and RTLB at REC10 (p = 1.0), remaining reduced in the RTUB during recovery (p < .05). Regarding the upper limbs, Tsk increased more markedly in the RTUB versus RTWB during the recovery period (p < .05); in the RTLB, biceps-Tsk remained below baseline over time (p < .05), whereas the forearm-Tsk was restored at REC10 (p = 1.0). Conclusion: Manipulating the muscle groups involved in rowing alters the Tsk response within equal ROI. Exercise-induced Tsk changes can reflect local hemodynamic and thermoregulatory adjustments.

Can Adipose Tissue Influence the Evaluation of Thermographic Images in Adolescents?

Infrared thermography (IRT) is a technology easy to use for clinical purposes as a pre-diagnostic tool for many health conditions. However, the analysis process of a thermographic image needs to be meticulous to make an appropriate decision. The adipose tissue is considered a potential influence factor in the skin temperature (Tsk) values obtained by IRT. This study aimed to verify the influence of body fat percentage (%BF) on Tsk measured by IRT in male adolescents. A total of 100 adolescents (16.79 ± 0.97 years old and body mass index of 18.41 ± 2.32 kg/m²) was divided into two groups through the results of a dual-energy X-ray absorptiometry analysis: obese (n = 50, %BF 30.21 ± 3.79) and non-obese (n = 50, %BF 11.33 ± 3.08). Thermograms were obtained by a FLIR T420 infrared camera and analyzed by ThermoHuman® software version 2.12, subdividing the body into seven regions of interest (ROI). The results showed that obese adolescents presented lower mean Tsk values than the non-obese for all ROIs (p < 0.05), with emphasis on the global Tsk (0.91 °C) and anterior (1.28 °C) and posterior trunk (1.18 °C), with "very large" effect size values. A negative correlation was observed in all the ROI (p < 0.01), mainly in the anterior (r = -0.71, p < 0.001) and posterior trunk (r = -0.65, p < 0.001). Tables of thermal normality were proposed for different ROIs according to the classification of obesity. In conclusion, the %BF affects the registered Tsk values in male Brazilian adolescents assessed by IRT.

Effects of Resistance Training on Skin Temperature and Its Relationship with Central Nervous System (CNS) Activation.

The aim of this work was to relate the activation of the sympathetic and parasympathetic nervous systems with the skin temperature (Tsk) of the lower limbs after a resistance training exercise. Under controlled conditions, the average Tsk in the areas of the anterior and posterior thighs, knees and legs was obtained with a thermal imager and the parasympathetic and sympathetic activation was registered with an Omegawave® device on 20 healthy and trained male volunteers (25.39 ± 8.21 years) before exercise, immediately after standard resistance training (3 exercises (2 quadriceps + 1 hamstrings) × 4 sets × 10 repetitions (70% 1RM), 90-sec recovery) and after 20 min of recovery. The results showed a significant effect of exercise and recovery on Tsk in all regions of interest (ROIs) considered (p < 0.05) and strong inverse relationships between sympathetic and parasympathetic activation values. Significant results were found for the total variation of Tsk (p < 0.05) with highly positive values for subjects with lower sympathetic activation and almost null or even negative values for those with higher sympathetic activation. Sympathetic activity was a significant predictor of total Tsk variation in the anterior thigh, posterior thigh and anterior knee but not in the posterior knee, anterior leg, and posterior leg. Baseline Tsk was a significant predictor of total Tsk variation the all ROIs except in the posterior knee. Tsk measured by thermography could be used to estimate the level of participation of muscle areas in exercise and registering the level of sympathetic activation before exercise could be interesting in predicting the athlete's physiological response to strength training.

Air shooting competition effects on visual skills depending on the sport level.

Olympic shooting is a sport with high demands of accuracy. Minimal visual errors could be related to performance losses. However, not all visual skills have been studied in depth in this sport. The main objectives of this study were to compare differences in shooters' visual skills by level and to analyze the competition effect on them. Sixty-six participants were distributed in three groups (non-athletes, elite and non-elite). Eleven visual variables were tested in four skills groups (visual acuity, heterophoria, accommodation functions and other visual skills). The data were collected through a pre- and post-competition simulation test. The results of the study showed differences between groups by shooting sport level. In general, shooters had higher visual acuity values than non-athletes p < .001 with large size effects (d between 1.01 and 2.35), and elite shooters presented higher values of accommodation than non-elite shooters p < .05 with large size effects (d between 0.88 and 0.97). Furthermore, different visual skills were modified after competition depending on the shooting level. Specifically, visual accommodation skills were only improved in elite shooters. Finally, our study suggests that elite shooters employ different visual strategies or skills to non-elite shooters and that shooting activity is closely related to some specific visual skills. This aspect should be considered by coaches in the design of optimal visual trainings and improve the shooters' performance.Highlights Shooters showed better acuity skills than non-athletes.Shooting activity seems to improve visual acuity skills, binocular visual time and eye-hand coordination in non-elite shooters, and accommodation and eye-hand coordination in elite shooters immediately after the competition simulation.Elite shooters employ different visual strategies or skills to non-elite shooters.Non-dominant eye occlusion may benefit binocular vision recovery by inhibiting aiming action and the use of accommodative flexibility could be related to the QE during the shot.

Comparison of Adherence to Mediterranean Diet between Spanish and German School-Children and Influence of Gender, Overweight, and Physical Activity.

BACKGROUND: Poor dietary habits and low levels of physical activity (PA) have a strong tendency to track from childhood into adulthood. The Mediterranean Diet (MD) is known to be extremely healthy, associated with lower BMI and a lower risk of obesity in children and adolescents. Therefore, adherence to the MD was compared between Spanish (n = 182) and German (n = 152) children aged 10 to 13 years to examine a possible more "westernized" diet in Spain with a non-Mediterranean country, that traditionally prefers a "Western diet" and to determine the association between adherence to the MD and gender, body composition, and PA levels. METHODS: In the German observational longitudinal cohort study and the Spanish cohort study, body composition and questionnaires (KIDMED, Diet Quality (IAES)) were obtained, and accelerometers (Actigraph) were applied to detect PA. RESULTS: Girls had higher BMI-standard deviation score (SDS) than boys and Spanish girls were less active than boys. Differences were detected in MD habits, such as favorable fruit-, vegetables-, fish-intakes, and dairy products in Spanish children and unfavorable consumptions of fast food, processed bakery goods, candies, and sweet beverages in German children. Independently of country, girls, children with lower BMI-SDS and children with higher PA level were related with better diet quality. CONCLUSION: Spanish children showed higher adherence to MD and diet quality (IAES) compared to German children, but there was a trend toward a more "westernized" diet. Gender, body composition, and PA influenced nutrition regardless of country.

Correction: García-Aliaga et al. Comparative Analysis of Soccer Performance Intensity of the Pre-Post-Lockdown COVID-19 in LaLiga™. Int. J. Environ. Res. Public Health 2021, 18, 3685.

The authors wish to make the following corrections to this paper [...].

Sustainable Food Support during an Ultra-Endurance and Mindfulness Event: A Case Study in Spain.

The present industrial food-production system is not suitably ecological for the environment. Mindful nutrition in sport is a relevant emergent sub-discipline that could help reduce environmental degradation. This case study describes a sustainable support diet during an ultra-endurance running (UR) event called the "Indoor Everest Challenge". This UR challenge involved attaining the altitude of Mount Everest (8849 m) in a simulated way, in less than 24 h, without using ultra-processed food and without wasting plastics. During this challenge, a male athlete (34 years, weight: 78 kg, and height: 173 cm) wore a SenseWear Armband® (BodyMedia Inc., Pittsburg, PA, USA) accelerometer on his right arm to estimate energy expenditure. To supply his nutritional requirements, the athlete consumed only specially prepared homemade and organic food. All consumption was weighed and recorded in real-time; we determined nutrients using two databases: a food composition software, Dial Alce Ingenieria® (Madrid, Spain), to measure energy and macro- and micro-nutrients, and Phenol Explorer Database® (INRA Institut National de Recherche pour l'Alimentation, Paris, France) precisely to determine polyphenolic content. Most energy intake (up to 96%) came from plant foods. We found that subject consumed 15.8 g/kg-1/d-1 or 1242 g of carbohydrates (CHO), (2.4 g/kg-1/d-1) or 190 g of proteins (P), and 10,692 mL of fluid. The total energy intake (7580 kcal) showed a distribution of 65% CHO, 10% P, and 25% lipids (L). Furthermore, this sustainable diet lead to a high antioxidant intake, specifically vitamin C (1079 mg), vitamin E (57 mg), and total polyphenols (1910 mg). This sustainable approach was suitable for meeting energy, CHO, and P recommendations for UR. Physical and mental training (mindfulness) were integrated from the specific preliminary phase to the day of the challenge. The athlete completed this challenge in 18 h with a low environmental impact. This sports event had an educational component, as it awakened curiosity towards food sustainability.

Effects of conventional and sugar-free energy drinks intake in runners: a double-blind, randomized, placebo-controlled crossover clinical trial.

BACKGROUND: This study evaluated the effects of two types of energy drinks (ED) intake in trained runners. METHODS: A double-blind randomized placebo-controlled clinical trial was conducted over 6 weeks. Participants and beverages were allocated by randomization. Twelve men 23±2.6 years, 177±3.4 cm, 74.4±5.5 kg, VO2max=59.8±5.5 mL·(kg.min)-1] ingested either a conventional energy drink containing carbohydrates and 3 mg·kg-1 of caffeine, (ED1), a sugar-free energy drink 3 mg·kg-1 of caffeine (ED2), or a carbohydrate-containing, decaffeinated placebo (PL) 40-minutes before an exercise protocol. Sprint time, rate of perceived exertion (RPE), respiratory exchange ratio (RER), blood pressure (BP), heart rate and plasmatic glucose were evaluated during the experimental protocol. RESULTS: Performance improved after consuming both ED (P<0.004 ED1 and P=0.001 ED2) with lower RPE (P<0.05 for ED1 and P<0.05 for ED2) compared to PL. Consumption of ED2 decreased RER values at 0-5 minutes and 40-45 minutes (P<0.001), and ED1 increased systolic BP (P<0.05) during exercise compared to PL. There were no differences in the evaluated parameters between EDs (P>0.05). CONCLUSIONS: Consumption of conventional or sugar free ED represents a valid ergogenic strategy to improve acute performance with reduction of RPE. However, intake of a conventional ED warrants caution, mainly because the effects on systolic BP.