The literature suggests that high-intensity interval training (HIIT) is more effective than moderate-intensity continuous training (MICT) to improve functional ability. However, there is no evidence on including HIIT in a circuit programme (HIICT). Our objective was to determine what type of training (HIICT or MICT) induces greater adaptations in the functional ability and body mass index of middle-aged and older women. The study used a quasi-experimental randomized controlled trial with 54 participants (age = 67.8 ± 6.2 years). Participants were randomly allocated to HIICT (n = 18), MICT (n = 18) or a non-exercise control group (CG; n = 18). The participants in the HIICT or MICT groups trained twice a week (1 h/session) for 18 weeks. Forty-one subjects were analysed (HIICT; n = 17, MICT; n = 12, CG; n = 12). Five subjects presented adverse events during the study. Strength, gait, cardiorespiratory fitness, balance and body mass index were measured. A significant training x group interaction was found in the arm curl test, where HIICT was statistically better than MICT and CG. Likewise, HIICT was statistically better than the CG in the BMI interaction. In lower limb strength, gait/dynamic balance and cardiorespiratory fitness, both HIICT and MICT were statistically better than the CG. In conclusion, HIICT generated better adaptations in upper limb strength than MICT. Likewise, HIICT generated better adaptations in body mass index than CG. Finally, both HIICT and MICT had a similar influence on strength, cardiorespiratory fitness and gait/dynamic balance.

High-intensity interval training (HIIT) has similar or better effects than moderate-intensity continuous training (MICT) in increasing peak oxygen consumption (VO_2max), however, it has not been studied when HIIT is applied in a circuit (HIICT). The aim of this study was to compare the effects of a HIICT versus MICT on VO_2max estimated (VO_2max-ES), heart rate (HR) and blood pressure (BP) of middle-aged and older women. A quasi-experimental randomized controlled trial was used. Fifty-four women (67.8 ± 6.2 years) were randomized to either HIICT (n = 18), MICT (n = 18) or non-exercise control group (CG; n = 18) for 18 weeks. Participants in HIICT and MICT trained two days/week (one hour/session). Forty-one participants were assessed (HIICT; n = 17, MICT; n = 12, CG; n = 12). Five adverse events were reported. Cardiorespiratory fitness, HR and BP were measured. The tests were performed before and after the exercise intervention programs. VO_2max-ES showed significant training x group interaction, in which HIICT and MICT were statistically superior to CG. Moreover, HIICT and MICT were statistically better than CG in the diastolic blood pressure after exercise (DBP_ex) interaction. For the systolic blood pressure after exercise (SBP_ex), HIICT was statistically better than CG. In conclusion, both HIICT and MICT generated adaptations in VO_2max-ES and DBP_ex. Furthermore, only HIICT generated positive effects on the SBP_ex. Therefore, both training methods can be considered for use in exercise programs involving middle-aged and older women.

Physiological training responses depend on sympathetic (SNS) and parasympathetic nervous system (PNS) balance. This activity can be measured using heart rate variability (HRV). Such a measurement method can favor individualized training planning to improve athletes’ performance. Recently, HRV-guided training has been implemented both on professional and amateur sportsmen and sportswomen with varied results. There is a dearth of studies involving professional endurance athletes following a defined HRV-guided training protocol. The objectives of the proposed protocol are: (i) to determine changes in the performance of high-level athletes after following an HRV-guided or a traditional training period and (ii) to determine differences in the athletes’ performance after following both training protocols. This will be a 12-week cluster-randomized controlled protocol in which professional athletes will be assigned to an HRV-based training group (HRV-G) or a traditional-based training group (TRAD-G). TRAD-G will train according to a predefined training program. HRV-G training will depend on the athletes’ daily HRV. The maximal oxygen uptake (VO_2max) attained in an incremental treadmill test will be considered as the primary outcome. It is expected that this HRV-guided training protocol will improve functional performance in the high-level athletes, achieving better results than a traditional training method, and thus providing a good strategy for coaches of high-level athletes.

Background: The Balance Evaluation Systems Test (BESTest) and two abbreviated versions, Mini-BESTest and Brief-BESTest are used to assess functioning of balance control systems. Its reliability across different populations remains to be determined. Objective: The present study followed reliability generalization procedures to estimate an average internal consistency and inter and intra-rater reliability for the BESTest, Mini-BESTest and Brief-BEStest. In this study, the heterogeneity of reliability coefficients in each instrument is evaluated. If heterogeneity is significant, a moderator analysis is performed to identify the characteristic which explains such variability. Methods: A search of the PubMed, Embase, PsycINFO, Web of Science, Scopus and CINAHL databases was carried out to February 10^th 2024. Two reviewers independently selected empirical studies published in English or Spanish that applied the BESTest, Mini-BESTest and/or Brief-BESTest and reported any reliability coefficient and/or internal consistency with data at hand. Results: Sixty-four studies reported any reliability estimate BESTest, Mini-BESTest and/or Brief-BESTest scores (N. = 5225 participants). Mean Cronbach alpha for the Mini-BESTest and Brief-BESTest (total score = 0.92) indicating no variability in estimated internal consistency. Likewise, no variability was obtained for inter-rater and intra-rater mean agreement of the BESTest (ICC = 0.97; 0.94), Mini-BESTest (ICC = 0.95; 0.94) and Brief-BESTest (ICC = 0.96; 0.95). Mean scores, standard deviation of scores, mean age, gender, population type, mean history of the disorder, disease, raters´ experience, number of raters, rater formation, continent of study and design type presented statistically significant relationships with ICC and/or Cronbach´s alpha for BESTest and the two abbreviated versions. Conclusions: The mean intraclass correlations and Cronbach alpha obtained for BESTest, Mini-BESTest and Brief-BESTest exhibited an excellent inter and intra-rater reliability and internal consistency. The average reliability obtained three scales adequate to be applied for screening balance problems in different populations. Some continuous and categorical moderator variables increase reliability and internal consistency of these scales.

Background: The use of normobaric hypoxia can bring benefits to sports performance because it improves haematological parameters and/or physical activity tests. Our objective was to conduct a systematic review so as to analyse the methods used in hypoxia and to detect its effects on middle- and/or long-distance runners. Methods: Research was conducted using five electronic databases (PubMed, SportDiscus, Cochrane Library, Scopus and PEDro) until December 2021. The methodological quality of the included studies was assessed using the PEDro scale. Results: Having analysed 158 studies, 12 were chosen for the qualitative and quantitative synthesis. A significant improvement on time until exhaustion was detected, and oxygen saturation decreased after the intervention. There were no significant changes in the 3000-metre time trial or in the haematocrit percentage. The changes in percentage of reticulocytes, heart rate, maximal heart rate, lactate concentration and erythropoietin were heterogeneous between the different research studies. Conclusion: short exposure (less than 3 h to normobaric hypoxia significantly increases the time to exhaustion). However, longer exposure times are necessary to increase haemoglobin. Altitude and exposure time are highly heterogeneous in the included studies.

Introduction: Near infrared spectroscopy (NIRS) is a non-invasive technique that is used in the assessment of tissue oxygenation and the monitoring of physical activity. Objective: To determine the influence of sexual, anthropometric and ergospirometric factors on muscle oxygenation of the quadriceps and gastrocnemius, obtained by NIRS during a stress test. Methods: Twenty healthy subjects participated in this study (10 women). Two Humon Hex® devices were placed on the dominant side of the quadriceps and gastrocnemius muscles to measure muscle oxygen saturation (SmO2). The stress test was performed on a treadmill with electrocardiographic control and measurement of oxygen consumption. SmO2 was obtained at rest and after maximum effort during the stress test. In addition, the height, weight, skinfold and waist contour were measured. Bioimpedance was used to obtain the percentages of fat mass and muscle mass, which were used to calculate the relative fat mass (RFM). Results: The SmO2 of both muscles at rest is higher in males than in females. At maximum effort, the SmO2 of the quadriceps is similar in both groups. The SmO2 of both muscles is positively related to height, body mass, percentage of mass muscle and waist contour, and negatively with percentage of mass fat, RFM and skinfold thickness. The negative correlation between fat percentage and oxygen saturation is more evident in females. It was observed that the variables that quantify maximum effort are not related to the SmO2 values, except for the correlation between HR max and SmO2 of the gastrocnemius muscle in males. Conclusion: The SmO2 of recreational athletes is influenced by the location of the device and the fat mass of the subjects. The biggest differences between the sexes are in the gastrocnemius muscle. Level of Evidence II; Diagnostic Studies - Investigating a Diagnostic Test .