Effect of High-Intensity Interval Treadmill Exercise on Subsequent Lower and Upper Limb Strength Performance

Purpose: The aim of this study was to analyze the acute effect of a treadmill high-intensity interval protocol on subsequent upper body and lower body strength exercise performance. Method: Sixteen young men had their maximal aerobic capacity and one-repetition maximum (1RM) determined and underwent four randomized conditions: a half-squat control session; a bench press control session; a treadmill interval protocol followed by a half-squat experimental session; and a treadmill interval protocol followed by a bench press experimental session. During the control sessions, four sets to failure for each exercise were performed at 80% of 1RM. In the experimental sessions, participants performed eight sprints of 40 s at 100% velocity of maximal oxygen uptake with 20 s of passive interval between them, followed by the same strength exercise protocol of the control sessions. The number of repetitions during each protocol and participants' heart rate (HR),and blood lactate concentration ([lac]) were compared pre and post protocols and exercises. Results: Fewer repetitions were completed in the experimental session compared to the control sessions (p < .001). Moreover, the reduction in number of repetitions performed was more evident in half-squat compared to bench press (p = .018). HR was higher at the end of sessions with the interval protocol for both exercises (p < .001). The [lac] was higher at the end of session with the interval protocol for half-squat (p = .003). Conclusions: These findings suggest that previous high-intensity interval running may impair subsequent strength exercise performance, but the magnitude of the negative effect is greater in the lower limbs.

Water-Based Training Programs Improve Functional Capacity, Cognitive and Hemodynamic Outcomes? The ACTIVE Randomized Clinical Trial

Purpose: To compare the effects of 16 weeks of aerobic training (AT) to 8 weeks of AT followed by 8 weeks of combined training (CT), as well as to a control group (CG), on the functional, cognitive and hemodynamic responses of older women exercising in the aquatic environment. Materials and Methods: The study is a three-armed parallel randomized controlled clinical trial. For this, 52 older women were first randomized in an aerobic training (AT; n = 35) or control group (CG; n = 17). After 8 weeks of intervention, participants from AT group were again randomized into another 8-week period of either AT (n = 17) or combined training (CT; n = 18). AT was performed at the percentage of the heart rate corresponding to the anaerobic threshold, resistance training was performed with sets at maximal effort and the control group performed low-intensity therapeutic exercises in water. All outcomes were assessed before (week 0) and after the intervention (week 17). In addition, some outcomes were also investigated in the middle timepoint (week 9). Generalized Estimating Equations (GEE) and Bonferroni post-hoc tests (α = 0.05) were used to compare timepoints and groups. Results: All groups similarly improved functional capacity (3-11%) and blood pressure (-4 to -10%), whereas cognitive function was not modified for any group. Conclusion: Water-based training programs and therapeutic exercises (i.e., CG) improve functional capacity and blood pressure responses in older women. Clinical Trials NCT03892278.

Exercise intervention does not reduce the likelihood of VO2max underestimation in older adults with hypertension

The present study aimed to investigate whether training status would influence the capacity of a verification phase (VER) to confirm maximal oxygen uptake (VO₂max) of a previous graded exercise test (GXT) in individuals with hypertension. Twelve older adults with hypertension (8 women) were recruited. Using a within-subject design, participants performed a treadmill GXT to exhaustion followed by a multistage VER both before and after a 12-wkcombined exercise training programme. Individual VO₂max, respiratory exchange ratio (RER), maximal heart rate (HR_max), and rating of perceived exertion (RPE) were measured during both GXT and VER tests. Absolute and relative VO₂max values were higher in VER than in GXT at baseline, but only absolute VO₂max differed between bouts post-intervention (all p < 0.05). Individual VO₂max comparisons revealed that 75% of the participants (9/12) achieved a VO_2max value that was ≥3% during VER both before (range: +4.9% to +21%) and after the intervention (range: +3.4% to +18.8%), whereas 91.7% (11/12) of the tests would have been validated as a maximal effort if the classic criteria were employed. A 12-wk combined training intervention could not improve the capacity of older adults with hypertension to achieve VO₂max during a GXT, as assessed by VER.

Quality of life responses after combined and aerobic water-based training programs in older women: a randomized clinical trial (ACTIVE Study)

BACKGROUND

Quality of life (QoL) is an important health index for older adults.

AIM

The aim of this study was to compare the effects of 16 weeks of aerobic training to 8 weeks of aerobic followed by 8 weeks of combined (i.e., resistance and aerobic exercises) training, as well as to a control group on the QoL of older women exercising in the aquatic environment.

METHODS

52 older women were first randomized to either aerobic training (n = 35) or a control group (n = 17). After 8 weeks of intervention, participants initially assigned to the aerobic training group were again randomized to either 8 additional weeks of aerobic (n = 17) or combined training (n = 18). Aerobic training was performed at the heart rate percentage associated with the anaerobic threshold, while resistance training sets were performed at maximal effort. The control group performed low-intensity water-based therapeutic exercises. QoL was assessed before (week 0) and after the intervention (week 17) using the WHOQOL-BREEF and WHOQOL-OLD questionnaires. Generalized Estimating Equations (GEE) and Bonferroni post hoc tests (α = 0.05) were used to compare time points and groups.

RESULTS

QoL improved significantly only in the training groups after the 16-week training intervention, whereas it remained unchanged in the control group. In addition, autonomy, environment, and present, past and future activities domains were more impacted after combined training.

CONCLUSION

QoL improved only in the water-based training groups, and the addition of resistance exercises to the training program resulted in additional benefits to autonomy, environment, and past, present, and future activities domains.

TRIAL REGISTRATION

Clinical Trials NCT03892278.

Cardiorespiratory Parameters Comparison Between Incremental Protocols Performed in Aquatic and Land Environments by Healthy Individuals: A Systematic Review and Meta-Analysis

BACKGROUND

Physical properties of water cause physiological changes in the immersed human body compared with the land environment. Understanding the magnitude of cardiorespiratory alterations might ensure adequate intensity control during aquatic exercise programs.

OBJECTIVE

We aimed to compare the oxygen uptake (VO₂), heart rate (HR), and rating of perceived exertion (RPE) parameters during aquatic and land incremental tests.

METHODS

Four databases (PubMed, LILACS, EMBASE, and SPORTDiscus) were searched in September 2020. Eligibility criteria included studies in a crossover design comparing aquatic and land incremental tests for healthy individuals with at least one of the following parameters: VO₂ (maximal, VO_2max; anaerobic threshold, VO_2AT), HR (HR_max; HR_AT), and RPE (RPE_max; RPE_AT). The random-effects meta-analysis included mean difference and 95% confidence interval for VO₂ and HR or standardized mean difference for RPE. The Joanna Briggs Institute Critical Appraisal tool was adapted to assess methodological quality.

RESULTS

Twenty-eight studies were eligible and included in the meta-analysis. Aquatic protocols showed lower values compared with land for VO_2max (- 7.07 mL.kg^-1.min^-1; - 8.43 to - 5.70; n = 502), VO_2AT (- 6.19 mL.kg^-1.min^-1; - 7.66 to - 4.73; n = 145), HR_max (- 11.71 bpm; - 13.84 to - 9.58; n = 503), and HR_AT (- 15.29 bpm; - 19.05 to - 11.53; n = 145). RPE_max (0.01; - 0.16 to 0.18; n = 299) and RPE_AT (- 0.67; - 1.35 to 0.02; n = 55) values were similar between aquatic and land protocols.

CONCLUSIONS

Our study reinforces the specificity of the environment during incremental tests for prescribing exercises based on physiological parameters as VO₂ and HR parameters presented lower values in aquatic protocols than land protocols. Conversely, RPE seems an interchangeable measure of exercise intensity, with similar values during the protocols in both environments. Substantial levels of heterogeneity were present for the VO_2max and HR_max meta-analyses, and as such, results should be interpreted with attention. PROTOCOL REGISTRATION: This study was registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD42020212508).

Aerobic and combined water-based trainings in older women: effects on strength and cardiorespiratory outcomes

BACKGROUND

The aim of the present study was to investigate the muscular and cardiorespiratory adaptations of two water-based training programs in older women.

METHODS

Volunteers were divided between a water-based aerobic training (WBA; n=13), water-based combined training (WBC; n=11) or an active control group (CG; n=9) and those assigned to WBA and WBC exercised twice a week for 12 weeks. All outcomes of interest were assessed prior and after the intervention. The data were analyzed using Generalized Estimating Equations (GEE), and Bonferroni post-hoc test (α = 0.05). Aerobic training was performed at the percentage of the heart rate corresponding to the anaerobic threshold and resistance training during WBC was performed with sets at maximal effort.

RESULTS

Improvements were observed for the maximal knee extension dynamic strength (1RM) and oxygen uptake (VO2) corresponding to the second ventilatory threshold for both WBA and WBC (1RM: 16 ± 12% vs. 15 ± 16%; VO2: 20 ± 24% vs. 23 ± 13%, respectively), whereas VO2 peak improved in all three groups (WBA: 23 ± 21%; WBC: 18 ± 9%; CG: 7 ± 16%). No increase was found for horizontal chest press 1RM (p > 0.05).

CONCLUSIONS

These results suggest that WBA, WBC and CG are effective to improve cardiorespiratory fitness, however, only water-based training programs (WBA and WBC) appear capable of improving the maximal strength of the lower limbs.

Anaerobic Threshold in a Water-Based Exercise: Agreement Between Heart Rate Deflection Point and Lactate Threshold Methods

ABSTRACT

Alberton, CL, Andrade, LS, Pinheiro, RB, and Pinto, SS. Anaerobic threshold in a water-based exercise: agreement between heart rate deflection point and lactate threshold methods. J Strength Cond Res 35(9): 2472-2478, 2021-The purpose of this study was to compare and assess the agreement of the heart rate (HR) and rating of perceived exertion (RPE) corresponding to the anaerobic threshold (AT) between HR deflection point (HRDP) and lactate threshold (LT) methods during a water-based exercise in young men. Sixteen young men (24 ± 6 years) performed the experimental protocol, which comprised the performance of a maximal incremental test during the water-based stationary running exercise. The initial cadence corresponded to 90 b·min-1, with 10 b·min-1 increases every 3 minutes up to exhaustion. Heart rate was monitored every 30 seconds while blood lactate concentrations and RPE were measured at the end of each 3-minute bout. Anaerobic threshold was identified by HRDP and LT methods by experienced physiologists. Paired Student's t-test, Bland-Altman analysis, and Pearson correlation were used for data analysis (α = 0.05). As results, there was agreement between HRDP and LT methods for HR, while RPE presented significant higher values for the HRDP method, resulting in an absence of acceptable agreement between methods. In addition, strong relationships (p ≤ 0.001) were verified between methods of AT determination for HR (r = 0.786) and RPE (r = 0.916). Therefore, based on the agreement between HRDP and LT methods, the HR determined by HRDP may be a valid parameter used for the intensity prescription of water-based stationary running exercise in young men during water aerobics programs and may be considered more reliable than RPE.

Maximal Oxygen Uptake Is Underestimated during Incremental Testing in Hypertensive Older Adults: Findings from the HAEL Study

PURPOSE

The present cross-sectional study aimed to investigate whether a maximal oxygen uptake (V˙O2max) verification phase (VER) could improve the accuracy of a previous graded exercise test (GXT) to assess individual V˙O2max in hypertensive individuals.

METHODS

Thirty-three older adults with hypertension (24 women) taking part in the Hypertension Approaches in the Elderly Study (NCT03264443) were recruited. Briefly, after performing a treadmill GXT to exhaustion, participants rested for 10 min and underwent a multistage VER to confirm GXT results. Individual V˙O2max, RER, maximal heart rate (HRmax), and RPE were measured during both GXT and VER tests. Mean values were compared between bouts using paired sample t-tests, and V˙O2max was also compared between GXT and VER on an individual basis.

RESULTS

Testing was well tolerated by all participants. Both absolute (P = 0.011) and relative (P = 0.014) V˙O2max values were higher in VER than that in GXT. RER (P < 0.001) and RPE (P = 0.002) were lower in VER, whereas HRmax (P = 0.286) was not different between the two trials. Individual V˙O2max comparisons revealed that 54.6% of the participants (18/33) achieved a V˙O2max value that was ≥3% during VER (mean = 13.5%, range = +3% to +22.1%, ES = 0.062), whereas 87.9% (29/33) of the tests would have been validated as a maximal effort if the classic criteria were used (i.e., V̇O2 plateau or at least two secondary criteria).

CONCLUSION

In sedentary older individuals with hypertension, GXT to exhaustion underestimated V˙O2max in more than half of tested participants, even when established, but criticized criteria were used to confirm whether a maximal effort was attained. Using VER after GXT is a quick approach to assist with the verification of an individual's V˙O2max.

High-intensity interval running impairs subsequent upper limb strength performance

BACKGROUND

This study compared the effect of treadmill running on subsequent upper limb exercise performance in young men.

METHODS

Seventeen young men (24.8±5.2 years) completed a: 1) bench press resistance exercise control session; 2) treadmill interval running protocol followed by the bench press session; and 3) treadmill continuous running protocol followed by the bench press session. Four sets of the bench press exercise were performed at 80% of 1RM up to volitional failure. In the interval protocol, eight sprints of 40s at 100% of the velocity of maximal oxygen uptake, with 20s of passive interval between them were performed, whereas in the continuous protocol 30-min of treadmill running at 90% of the heart rate corresponding to second ventilatory threshold was performed. The number of maximal repetitions completed in each set and condition was recorded and compared using a two-way repeated measures ANOVA.

RESULTS

The interval protocol (18.7±4.9 repetitions) resulted in a reduction in the number of bench press repetitions compared to the control protocol (21.4±5.4 repetitions) (P=0.002); whereas continuous running did not affect the bench press performance (20.6±4.4 repetitions). The total number of repetitions reduced from set to set in all protocols (P<0.001).

CONCLUSIONS

The results evidenced an impairment in the upper limb strength performance after high intensity interval, but not moderate intensity continuous running, which has implication for concurrent training planning and prescription.

Shell occupation by the hermit crab Dardanus insignis (Decapoda, Diogenidae) from the north Coast of São Paulo state, Brazil

The pattern of shell occupation by the hermit crab Dardanus insignis (Saussure, 1858) from the subtropical region of southeastern coast of Brazil was investigated in the present study. The percentage of shell types that were occupied and the morphometric relationships between hermit crabs and occupied shells were analyzed from monthly collections conducted during two years (from January 1998 to December 1999). Individuals were categorized according to sex and gonadal maturation, weighed and measured with respect to their cephalothoracic shield length (CSL) and wet weight (CWW). Shells were measured regarding their aperture width (SAW), dry weight (SDW) and internal volume (SIV). A total of 1086 hermit crabs was collected, occupying shells of 11 gastropod species. Olivancillaria urceus (Roding, 1798) was most commonly used by the hermit crab D. insignis, followed by Buccinanops cochlidium (Dillwyn, 1817), and Stramonita haemastoma (Linnaeus, 1767). The highest determination coefficients (r2 > 0.50, p < 0.01) were recorded particularly in the morphometric relationships between CSL vs. CWW and SAW vs. SIV, which are important indication that in this D. insignis population the great majority the animals occupied adequate shells during the two years analysed. The high number of used shell species and relative plasticity in pattern of shell utilization by smaller individuals of D. insignis indicated that occupation is influenced by the shell availability, while larger individuals demonstrated more specialized occupation in Tonna galea (Linnaeus, 1758) shell.

Reproductive features of the swimming crab Callinectes danae(Crustacea, Portunoidea) on the subtropical coast of Brazil: a sampling outside the estuary

The life cycle of the crab Callinectes danae is estuarine-dependent, and studies on aspects of their biology should also cover marine areas. The present study investigated the sexual maturity, as well as habitat preference by adults in different gonadal stages, and the crabs' reproductive periodicity outside the estuary. Three bays on the subtropical southeastern coast of Brazil were sampled monthly for two years. For each bay, six transects were established, four of them parallel to the beach line (5, 10, 15 and 20 m depth), as well as one transect in an exposed area, and another sheltered from the action of waves. The results showed that the pattern of spatio-temporal distribution of adults C. danae was similar in three bays, although the highest abundance was found in Ubatumirim. Females with developed gonads/ovigerous females were found in greater abundance than females with rudimentary/developing gonads, mainly in deeper transects. Although the areas sampled have different environmental characteristics, the reproductive pattern of the species did not change, showing continuous reproduction throughout, with more abundance of reproductive females on spring and summer. Males reached maturity at larger sizes than females in all three bays.

Differential habitat use by demographic groups of the redfinger rubble crab Eriphia gonagra (Fabricius, 1781)

The structurally diverse rocky shores along the northern coast of the state of São Paulo, Brazil, support a varied fauna and provide refuges for many organisms. Some of these environments allow for extensive microhabitats, among them the sand reefs formed by the polychaete Phragmatopoma lapidosa, which occupy much of this area. The beauty of the landscape attracts large numbers of tourists, who contribute to the damage to the sand reef colonies, causing an imbalance in the patterns of population distribution and of this ecosystem. We describe the structure and population biology of the redfinger rubble crab Eriphia gonagra, and investigated the differential occupation of the habitat by each demographic category of this species. Crabs were sampled monthly for two consecutive years on the rocky coast of Grande Beach, Ubatuba, São Paulo, during spring low tides. Sampling was carried out over an area of approximately 1200 m2, during two hours on the rock surface and another two hours on the sand reefs. A total of 1407 crabs were collected; 776 on the sand reef (SR) and 631 on the rocky shore (RO). The majority of juvenile crabs inhabited the SR, while adult crabs were equally distributed in both microhabitats. This study showed that the SR is a natural nursery ground for the establishment of the early juvenile stages of E. gonagra, which use the reefs as a refuge and food resource. Many other organisms (mollusks, echinoderms, polychaetes etc.) settle on the reefs, and these areas may be among the most important in maintaining benthic diversity in the region.

Angiogenic activity of Synadenium umbellatum Pax latex

Synadenium umbellatum Pax, popularly known as 'cola-nota', is a medicinal plant that grows in tropical regions. Latex of this plant is used to treat various diseases such as diabetes mellitus, Hansen s disease, tripanosomiases, leukemia and several malignant tumors. In the present study, the angiogenic activity of S. umbellatum latex was evaluated using the chick embryo chorioallantoic membrane (CAM) assay. Results showed significant increase of the vascular net (p < 0.05) compared to the negative control (H2O). The histological analysis was in accordance with the results obtained. In conclusion, our data indicate that S. umbellatum latex, under the conditions of this research, presented angiogenic effect.