Force Production and Coordination from Older Women in Water Fitness Exercises

The aim of this study was to compare bilateral propulsive forces and coordination while exercising at static and dynamic conditions in the water. A total of 27 older women (age: 65.1 ± 6.7 years old) performed the following exercises: (i) horizontal upper-limbs adduction (HA; static condition) and (ii) rocking horse (RH; dynamic condition) through an incremental protocol with music cadences from 105 up to 150 b·min−1. The duration of each trial was set at 30 second (sec). Propulsive peak force (in Newton, N) of dominant (PFD) and nondominant (PFND) upper limbs was retrieved using hand sensors coupled to a differential pressure system. Significant differences in force production were found between static and dynamic exercises at higher cadences (120, 135, and 150 b·min−1). The static condition elicited higher bilateral propulsive forces and a more symmetric pattern. The in-water static exercise with bilateral action from the upper limbs proved to be the most appropriate strategy for older women to work strength and to reduce asymmetries.

Training status affects between-protocols differences in the assessment of maximal aerobic velocity

Purpose Continuous incremental protocols (CP) may misestimate the maximum aerobic velocity (Vmax) due to increases in running speed faster than cardiorespiratory/metabolic adjustments. A higher aerobic capacity may mitigate this issue due to faster pulmonary oxygen uptake ($$\dot{V}$$ V ˙ O2) kinetics. Therefore, this study aimed to compare three different protocols to assess Vmax in athletes with higher or lower training status. Methods Sixteen well-trained runners were classified according to higher (HI) or lower (LO) $$\dot{V}$$ V ˙ O2max$$\dot{V}$$ V ˙ O2-kinetics was calculated across four 5-min running bouts at 10 km·h−1. Two CPs [1 km·h−1 per min (CP1) and 1 km·h−1 every 2-min (CP2)] were performed to determine Vmax$$\dot{V}$$ V ˙ O2max, lactate-threshold and submaximal $$\dot{V}$$ V ˙ O2/velocity relationship. Results were compared to the discontinuous incremental protocol (DP). Results Vmax, $$\dot{V}$$ V ˙ O2max, $$\dot{V}$$ V ˙ CO2 and VE were higher [(P < 0.05,(ES:0.22/2.59)] in HI than in LO. $$\dot{V}$$ V ˙ O2-kinetics was faster [P < 0.05,(ES:-2.74/ − 1.76)] in HI than in LO. $$\dot{V}$$ V ˙ O2/velocity slope was lower in HI than in LO [(P < 0.05,(ES:-1.63/ − 0.18)]. Vmax and $$\dot{V}$$ V ˙ O2/velocity slope were CP1 > CP2 = DP for HI and CP1 > CP2 > DP for LO. A lower [P < 0.05,(ES:0.53/0.75)] Vmax-difference for both CP1 and CP2 vs DP was found in HI than in LO. Vmax-differences in CP1 vs DP showed a large inverse correlation with Vmax, $$\dot{V}$$ V ˙ O2max and lactate-threshold and a very large correlation with $$\dot{V}$$ V ˙ O2-kinetics. Conclusions Higher aerobic training status witnessed by faster $$\dot{V}$$ V ˙ O2 kinetics led to lower between-protocol Vmax differences, particularly between CP2 vs DP. Faster kinetics may minimize the mismatch issues between metabolic and mechanical power that may occur in CP. This should be considered for exercise prescription at different percentages of Vmax.

Agreement between heart rate deflection point and maximal lactate steady state in young adults with different body masses

We examined the agreement between heart rate deflection point (HRDP) variables with maximal lactate steady state (MLSS) in a sample of young males categorized to different body mass statuses using body mass index (BMI) cut-off points. One hundred and eighteen young males (19.9 ± 4.4 years) underwent a standard running incremental protocol with individualized speed increment between 0.3 and 1.0 km/h for HRDP determination. HRDP was determined using the modified Dmax method called S.Dmax. MLSS was determined using 2-5 series of constant-speed treadmill runs. Heart rate (HR) and blood lactate concentration (La) were measured in all tests. MLSS was defined as the maximal running speed yielding a La increase of less than 1 mmol/L during the last 20 min. Good agreement was observed between HRDP and MLSS for HR for all participants (±1.96; 95% CI = −11.5 to +9.2 b/min, ICC = 0.88; P < 0.001). Good agreement was observed between HRDP and MLSS for speed for all participants (±1.96; 95% CI = −0.40 to +0.42 km/h, ICC = 0.98; P < 0.001). The same findings were observed when participants were categorized in different body mass groups. In conclusion, HRDP can be used as a simple, non-invasive and time-efficient method to objectively determine submaximal aerobic performance in nonathletic young adult men with varying body mass status, according to the chosen standards for HRDP determination.

Does the Preferred Walk-Run Transition Speed on Steep Inclines Minimize Energetic Cost, Heart Rate or Neither?

Humans prefer to walk at slow speeds and to run at fast speeds. In between, there is a speed at which people choose to transition between gaits, the Preferred Transition Speed (PTS). At slow speeds, it is energetically cheaper to walk and at faster speeds, it is cheaper to run. Thus, there is an intermediate speed, the Energetically Optimal Transition Speed (EOTS). Our goals were to determine: 1) how PTS and EOTS compare across a wide range of inclines and 2) if the EOTS can be predicted by the heart rate optimal transition speed (HROTS). Ten healthy, high-caliber, male trail/mountain runners participated. On day 1, subjects completed 0° and 15° trials and on day 2, 5° and 10°. We calculated PTS as the average of the walk-to-run transition speed (WRTS) and the run-to-walk transition speed (RWTS) determined with an incremental protocol. We calculated EOTS and HROTS from energetic cost and heart rate data for walking and running near the expected EOTS for each incline. The intersection of the walking and running linear regression equations defined EOTS and HROTS. We found that PTS, EOTS, and HROTS all were slower on steeper inclines. PTS was slower than EOTS at 0°, 5°, and 10°, but the two converged at 15°. Across all inclines, PTS and EOTS were only moderately correlated. Although EOTS correlated with HROTS, EOTS was not predicted accurately by heart rate on an individual basis.

Inter-Limb Symmetry at Simultaneous and Alternated Arms Flexion by the Elbow during Water Fitness Sessions

The aim was to compare the inter-limb symmetry between alternated and simultaneous arms flexion during water fitness sessions. Twenty-three elderly women were recruited to perform flexion by the elbow with different mechanical strategies: (a) simultaneous and (b) alternated. An incremental protocol was used, with four music cadences, starting at 105 beats per minute up to 150. The peak force of dominant and non-dominant upper-limbs was retrieved. A symmetry index (SI, %) was also used to quantify coordination. There were significant variations in force produced by the dominant and non-dominant limbs in most of the cadences in the alternated or simultaneous actions. Differences with a medium effect between upper-limbs were shown when moving simultaneously indicating that an alternated movement can be a more proper strategy to work with. Despite that, both strategies seemed to be characterized by an asymmetric pattern (SI from 20 to 30%), requiring full attention from water fitness practitioners.

Relación entre la potencia y velocidad en press de banca y la velocidad de lanzamiento de balón en jugadores profesionales de balonmano (Relationship between barbell power and velocity in bench press exercise and ball throwing velocity in professional ha

Los objetivos de este estudio fueron (a) analizar la relación existente entre la una repetición máxima (1-RM) en press de banca y la velocidad de lanzamiento en jugadores de balonmano U18 de nivel internacional y, (b) analizar qué variables del ejercicio del press de banca son más relevantes en el rendimiento específico (velocidad de lanzamiento del balón) durante el test de velocidad de lanzamiento (T3-Step). Dieciséis jugadores de la Selección Española de Balonmano Juvenil participaron en la presente investigación. Todos los sujetos realizaron un protocolo incremental en el ejercicio del press de banca, además del T3-Step de velocidad de lanzamiento del balón. Por un lado, se analizó la relación existente entre la velocidad media (Velmedia), velocidad media de la fase propulsiva (VelMFP), velocidad pico (Velpico), potencia media (Potmedia), potencia media de la fase propulsiva (PotMFP), y potencia pico (Potpico) en todo el espectro de cargas en relación con la velocidad de lanzamiento. También se realizaron los mismos análisis con la carga en donde se obtuvo la máxima potencia media (CargaMP). Los resultados mostraron, por un lado que el rango de correlación de la CargaMP, PotmediaMP, PotMFPMP y PotpicoMP y la velocidad de lanzamiento fueron de .61 (p= .012), .702 (p< .01), .734 (p< .01) y .63 (p< .01), respectivamente. El coeficiente de correlación de Pearson entre la 1-RM y la velocidad de lanzamiento fue de r = .61 (p < .01). En conclusión, las variables relevantes a nivel de rendimiento específico con la velocidad de lanzamiento fueron la 1RM, la CargaMP, la PotMFPMP y la VelMFPMP. Todas estas analizadas en función del 60% de la 1-RM. Abstract. The objectives of this study were (a) to analyze the relationship between one repetition maximum (1-RM) in free bench press exercise and ball throwing velocity in handball players U18 of international level and, (b) to analyze which variables of bench press exercise are more relevant in the specific performance during the ball throwing velocity test (T3-Step). Sixteen (n = 16) players of the Spanish Youth Handball Team participated in the present investigation. All subjects included performed an incremental protocol bench press exercise, in addition to the T3-Step. On the one hand, it analyzed the relationship between the mean velocity (Velmean), the mean velocity of propulsive phase (VelmeanPP), peak velocity (Velpeak), the average power (Powermean), the average power of the propulsive phase (PowermeanPP), and peak power (Powerpeak) over the entire spectrum of charges in relation to the launch speed. The same analyzes were also obtained with the load where the maximum average power (LoadMP). The results obtained, on the one hand that the correlation range of the LoadMP, PowermeanPP, PowerMPPMP and PowerpeakPP and ball throwing velocity were .61 (p = .012), .70 (p < .01), .73 (p < .01) and 0.63 (p < .01), respectively. The correlation coefficient between the 1-RM and ball throwing velocity was r = 0.61 (p< .01). In conclusion, the relevant variables at the specific performance level with the ball throwing velocity were 1-RM, LoadMP, PowerMFPMP and VelMFPMP. All these analyzed according to 60% of the 1-RM.

Does the Preferred Walk-Run Transition Speed on Inclines Minimize Energetic Cost, Heart Rate or Neither?

ABSTRACTHumans prefer to walk at slow speeds and to run at fast speeds. In between, there is a speed at which people choose to transition between gaits, the Preferred Transition Speed (PTS). At slow speeds, it is energetically cheaper to walk and at faster speeds, it is cheaper to run. Thus, there is an intermediate speed, the Energetically Optimal Transition Speed (EOTS). Our goals were to determine: 1) how PTS and EOTS compare across a wide range of inclines and 2) if the EOTS can be predicted by the heart rate optimal transition speed (HROTS). Ten healthy, high-caliber, male trail/mountain runners participated. On day 1, subjects completed 0° and 15° trials and on day 2, 5° and 10°. We calculated PTS as the average of the walk-to-run transition speed (WRTS) and the run-to-walk transition speed (RWTS) determined with an incremental protocol. We calculated EOTS and HROTS from energetic cost and heart rate data for walking and running near the expected EOTS for each incline. The intersection of the walking and running linear regression equations defined EOTS and HROTS. We found that PTS, EOTS, and HROTS all were slower on steeper inclines. PTS was slower than EOTS at 0°, 5°, and 10°, but the two converged at 15°. PTS and EOTS were only moderately correlated. Although EOTS correlated with HROTS, EOTS was not predicted accurately by heart rate on an individual basis.

Similar maximal oxygen uptake assessment from a step cycling incremental test and verification tests on the same or different day

The present study aimed to compare maximal oxygen uptake of a step incremental test with time to exhaustion verification tests (TLIM) performed on the same or different day. Nineteen recreationally trained cyclists (age: 23 ± 2.7 years; maximal oxygen uptake: 48.0 ± 5.8 mL·kg−1·min−1) performed 3 maximal tests as follows: (i) same day: an incremental test with 3-min stages followed by a TLIM at 100% of peak power output of the incremental test (TLIM-SAME) interspaced by 15 min; and (ii) different day: a TLIM at 100% of peak power output of the incremental test (TLIM-DIFF). The maximal oxygen uptake was determined for the 3 tests. The maximal oxygen uptake was not different among the tests (incremental: 3.83 ± 0.41; TLIM-SAME: 3.72 ± 0.42; TLIM-DIFF: 3.75 ± 0.41 L·min−1; P = 0.951). Seven subjects presented a variability greater than ±3% in both verification tests compared with the incremental test. The same-day verification test decreased the exercise tolerance (240 ± 38 vs. 310 ± 36 s) compared with TLIM-DIFF (P < 0.05). In conclusion, the incremental protocol is capable of measuring maximal oxygen uptake because similar values were observed in comparison with verification tests. Although the need for the verification phase is questionable, the additional tests are useful to evaluate individual variability. Novelty Step incremental test is capable of measuring maximal oxygen uptake with similar values during TLIM on the same or different day. Although the necessity of the verification phase is questionable, it can allow the determination of variability in maximal oxygen uptake.

Anaerobic Threshold Biophysical Characterisation of the Four Swimming Techniques

The anaerobic threshold (AnT) seems to be not only a physiologic boundary but also a transition after which swimmers technique changes, modifying their biomechanical behaviour. We expanded the AnT concept to a biophysical construct in the four conventional swimming techniques. Seventy-two elite swimmers performed a 5×200 m incremental protocol in their preferred swimming technique (with a 0.05 m·s−1 increase and a 30 s interval between steps). A capillary blood samples were collected from the fingertip and stroke rate (SR) and length (SL) determined for the assessment of [La], SR and SL vs. velocity inflexion points (using the interception of a pair of linear and exponential regression curves). The [La] values at the AnT were 3.3±1.0, 3.9±1.1, 2.9±1 .34 and 4.5±1.4 mmol·l−1 (mean±SD) for front crawl, backstroke, breaststroke and butterfly, and its corresponding velocity correlated highly with those at SR and SL inflection points (r=0.91–0.99, p<0.001). The agreement analyses confirmed that AnT represents a biophysical boundary in the four competitive swimming techniques and can be determined individually using [La] and/or SR/SL. Blood lactate increase speed can help characterise swimmers’ anaerobic behaviour after AnT and between competitive swimming techniques.

Effect of neuromuscular resistance training on the performance of 5-km runners

The study aimed to identify the effect of a neuromuscular resistance training protocol (NRTP) on the performance of 5-km distance runners. This study included 18 male runners (age=29.3±3.2 years, fat percentage=11.3±2.6%, body height=1.77±.04 m, body mass=73.4±4.4 kg, time in 5 km=20.6±2.4 min, training years=4.3±0.7 years). First, volunteers were anthropometrically evaluated, and they performed one-repetition maximum (1RM) 45º leg press (LP) strength test. Second, they performed an incremental protocol in the 45º LP to acquire the electromyographic threshold. Third, they completed a 5-km time trial run (5 km basal). In the fourth session, they performed NRTP in LP. And fifth, the 5-km time trial run was performed at 30 min, 48 h, 96 h, and 144 h post the NRTP intervention. A significant decrease (p≤.05) was observed when baseline values were compared with post 30 min and post 48 h (p=.02 and p=.04, respectively). However, there were significant positive differences in performance (p=.04 for time) when baseline values and post 144 h were analyzed. Therefore, it is concluded that the NRTP can be used by 5-km distance runners to improve their performance with a break of one week between the intervention and test.