Two Different Approaches to Dry-land Training Do Not Improve the Water Performance of Swimmers.

Literature diverges about the performance improvement after dry-land training. Thus, the objective of the present study was to compare the effect of two models of dry-land training. Twenty-nine swimmers were divided into three groups, combined strength and power training (PTG), only strength training (STG), and a control group (CG). Measurements were taken for six weeks, before dry-land exposure (M1), after four weeks of specific training with exposure to dry-land training by two groups (M2), and after two weeks of taper without exposure to dry-land training (M3). Strength in specific exercises, jumping tests, and 50, 100, and 200m freestyle performance were evaluated on M1 and M3, while hematological and strength parameters in tethered swimming were measured in M1, M2, and M3. PTG showed time-effect improvement for 200, 100, and 50m performance (p<0.014), CG for 200 and 100m (p<0.047), and STG only for 100m (p:0.01). No differences were found in Δ performance between groups. PTG showed improvement in the peak force of tethered swimming on M2 (p:0.019), followed by a decrease on M3 (p:0.003). PTG and STG also showed an increase in creatinine, lactate dehydrogenase (LDH), and creatine kinase (CK) after M2 (p<0.038). Finally, it was concluded that both dry-land training sessions could change hematological parameters and improve physical attributes on dry-land and tethered swimming tests without improving performance.

Influence of Acute and Chronic High-Intensity Intermittent Aerobic Plus Strength Exercise on BDNF, Lipid and Autonomic Parameters.

The purpose of the present study is two-fold. First, we evaluated whether 8-weeks of combined training (high-intensity intermittent plus strength training) may change brain derived neurotropic factor (BDNF) and lipid parameters (triacylglycerol, HDL-c and non-HDL) in a fasted state. Second, we investigated the effect of an acute session of high-intensity intermittent exercise followed by strength training on systemic BDNF and lipid parameters pre- and post 8-weeks of training. Twenty-one healthy and physically active men were divided into two groups: high-intensity intermittent exercise combined with strength training (HSG; n = 11) and control (CG; n = 10). The HSG exercised for one minute at 100% of speedVO2max (sVO2max) interspersed with one minute of passive recovery followed by strength training (8 exercises with 8-12 repetition maximum loads) for 8-weeks. Heart rate variability, blood pressure, lipid profile, and BDNF concentrations were measured in the fasted state pre- and post-exercise and before and after the 8-week training period. After 8-weeks of exercise training, there was an increase in spectral high frequency component (ms2) and RR interval (p < 0.05), a decreased spectral low frequency component (nu) and heart rate values (p < 0.05), an increase in HDL-c (p < 0.001), and lower BDNF concentrations (p < 0.001). These results suggest that 8-weeks of high-intensity intermittent exercise combined with strength exercise is an effective protective cardio-metabolic strategy capable of increasing HDL-c and BDNF concentrations after an acute exercise session. In the long-term, the modulation on BDNF and HDL-c concentrations may be a determining factor for protection against neurological and cardiovascular diseases.

Maximum Strength Development and Volume-Load during Concurrent High Intensity Intermittent Training Plus Strength or Strength-Only Training.

The purpose of this study was to compare maximal strength gains during strength training (ST) and concurrent training (CT) consisting of high-intensity intermittent training plus strength training over the course of a 12-week intervention. A secondary purpose was to examine the relationship between strength training volume and strength gain in both groups. Nineteen recreationally active males were divided into CT (n = 11) and ST (n = 8) groups. The CT group performed repeated 1 min efforts at 100% of maximal aerobic speed interspersed by 1 min of passive recovery until accumulating a total running distance of 5km followed by a strength session (consisting of three sets of seven exercises with loads of 8-12 repetition maximum) twice weekly for a period of 12 weeks. The ST group performed only strength training sessions during the same 12-week period. Strength training total volume-load (Σ repetitions x load) for the upper- and lower-body was computed, while maximal strength (1RM) was evaluated at baseline, week 8, and week 12. Lower-body volume-load over 12 weeks was not different between groups. Absolute 1RM increased in both groups at week 8 and week 12, while 1RM relative to body mass increased in both groups at week 8, but only ST increased relative maximum strength between week 8 and week 12. There was a statistically significant correlation between strength training lower-body volume-load and maximum strength change between baseline and week 8 for the CT group (r = 0.656), while no significant correlations were found for the ST group. In summary, executing high-intensity intermittent exercise twice a week before strength training did not impair maximal strength after 8 weeks, however, only ST demonstrated an increase in relative strength after 12 weeks.

Effect of Endurance Training on The Lactate and Glucose Minimum Intensities.

Due to the controversy about the sensitive of lactate minimum intensity (LMI) to training and the need to develop other tool for aerobic fitness evaluation, the purpose of this study was to analyze the sensitivity of glucose minimum intensity (GMI) and LMI to endurance training. Eight trained male cyclists (21.4 ± 1.9 years, 67.6 ± 7.5 kg and 1.72 ± 0.10 m) were evaluated twice, before and after 12 weeks of training. GMI and LMI were calculated, respectively, by the lowest blood glucose and lactate values attained during an incremental test performed after a hyperlactemia induction, and VO2max was determined during standard incremental effort. The training was prescribed in three different zones and controlled by heart rate (HR). The training distribution was equivalent to 59.7%, 25.0% and 15.3% below, at and above anaerobic threshold HR respectively. The anaerobic threshold evaluated by GMI and LMI improvement 9.89 ± 4.35% and 10.28 ± 9.89 respectively, after training, but the VO2max 2.52 ± 1.81%. No differences were found between GMI and LMI in pre (218.2 ± 22.1 vs 215.0 ± 18.6 W) and post (240.6 ± 22.9 vs 237.5 ± 18.8 W) training situations. LMI and GMI were sensitive to 12-week aerobic training in cyclist; thus, both protocols can be used to assess aerobic adaptation, athletes diagnostic and prescribe training.

Reduced leptin level is independent of fat mass changes and hunger scores from high-intensity intermittent plus strength training.

BACKGROUND: This study aimed to analyze the effects of high-intensity intermittent training (HIIT) plus strength training on body composition, hormone related to energy balance (leptin), and hunger scores in physically active non-obese men. METHODS: Sixteen men were allocated in two different groups, training group (N.=10) performed a combined HIIT (5 km, 1 minute of effort interspersed by 1 minute of rest in passive recovery) followed by strength exercise session (three sets, with load of 8-12 repetition maximum) twice a week, during 8 weeks, while control group (N.=6) did not suffer any intervention. Hunger scores, leptin concentrations and body composition were assessed. Body composition, fasting leptin and hunger score were compared through two-way analysis (group and period) with repeated measures in the second factor while leptin and hunger scores in exercise session pre- and post-8 weeks through two-way analysis (period and time of measurement) with repeated measures in the second factor. RESULTS: The fasting leptin decreased pre- to post-8week in training group (7.7±4.9 to 2.9±2.1 ng/mL; P=0.012). For leptin response to exercise session there was main effect of training period, with higher values pre- (6.5±3.9 ng/mL) than post-training (2.6±2.1 ng/mL; P<0.001). For hunger scores there was effect of time of measurement (P<0.001), decreasing after breakfast and increasing over the experiment. CONCLUSIONS: Combined HIIT plus strength training were able to promote alterations in a hormone related to energy balance independent of body composition and hunger index alterations in physically active non-obese men.

Taurine supplementation can increase lipolysis and affect the contribution of energy systems during front crawl maximal effort.

Taurine can affect the energy system metabolism, specifically the lipid metabolism, since an increase in lipid oxidation may promote carbohydrate savings. We hypothesized that taurine supplementation associated with high-intensity exercise could increase levels of lipolysis, benefiting swimmer performance. Nine male competitive swimmers performed two 400-m front crawl maximal efforts with a 1-week washout, and the athletes received 6 g of taurine (TAU) or placebo (PLA) supplementation 120 min before performing the effort. Oxygen consumption and the contribution of the energy systems were analyzed post effort using a Quark CPET gas analyzer. Blood samples were collected before, and 5 min post the effort for taurine and glycerol analysis. Immediately before and 3, 5, and 7 min post the effort, blood samples from the earlobe were collected to determine lactate levels. An increase of 159% was observed in taurine plasma levels 120 min post ingestion. Glycerol levels were higher in both groups post effort; however, the TAU condition promoted an 8% higher increase than the PLA. No changes were observed in swimmer performance or lactate levels; however, the percentage change in lactate levels (∆[La-]) was different (TAU: 9.36 ± 2.78 mmol L-1; PLA: 11.52 ± 2.19 mmol L-1, p = 0.04). Acute taurine supplementation 120 min before performing a maximal effort did not improve swimmer performance; however, it increased glycerol plasma levels and reduced both the ∆[La-] and lactic anaerobic system contribution.

Short-Term High- and Moderate-Intensity Training Modifies Inflammatory and Metabolic Factors in Response to Acute Exercise.

Purpose: To compare the acute and chronic effects of high intensity intermittent training (HIIT) and steady state training (SST) on the metabolic profile and inflammatory response in physically active men. Methods: Thirty recreationally active men were randomly allocated to a control group (n = 10), HIIT group (n = 10), or SST group (n = 10). For 5 weeks, three times per week, subjects performed HIIT (5 km 1-min at 100% of maximal aerobic speed interspersed by 1-min passive recovery) or SST (5 km at 70% of maximal aerobic speed) while the control group did not perform training. Blood samples were collected at fasting (~12 h), pre-exercise, immediately post, and 60 min post-acute exercise session (pre- and post-5 weeks training). Blood samples were analyzed for glucose, non-ester fatty acid (NEFA), and cytokine (IL-6, IL-10, and TNF-α) levels through a three-way analysis (group, period, and moment of measurement) with repeated measures in the second and third factors. Results: The results showed an effect of moment of measurement (acute session) with greater values to TNF-α and glucose immediately post the exercise when compared to pre exercise session, independently of group or training period. For IL-6 there was an interaction effect for group and moment of measurement (acute session) the increase occurred immediately post-exercise session and post-60 min in the HIIT group while in the SST the increase was observed only 60 min post, independently of training period. For IL-10, there was an interaction for training period (pre- and post-training) and moment of measurement (acute session), in which in pre-training, pre-exercise values were lower than immediately and 60 min post-exercise, in post-training period pre-exercise values were lower than immediately post-exercise and immediately post-exercise lower than 60 min post, it was also observed that values immediately post-exercise were lower pre- than post-training, being all results independently of intensity (group). Conclusion: Our main result point to an interaction (acute and chronic) for IL-10 showing attenuation post-training period independent of exercise intensity.

Anaerobic Contribution Determined in Swimming Distances: Relation with Performance.

Total anaerobic contribution (TAn) can be assessed by accumulated oxygen deficit, and through sum of glycolytic and phosphagen contribution which enable the evaluation of TAn without influences on mechanical parameters. However, little is known about the difference of TAn within swimming distances. Therefore, the objectives of the present study were to determine and compare the TAn in different performances using the backward extrapolation technique and amount of lactate accumulated during exercise, and relate it with swimming performance. Fourteen competitive swimmers performed five maximal front crawl swims of 50, 100, 200, 400, and 800 m. The total phosphagen (AnAl) and glycolytic (AnLa) contributions were assumed as the fast component of post-exercise oxygen consumption (EPOCFAST) and amount of blood lactate accumulated during exercise, respectively. TAn was the sum of AnAl and AnLa. Significantly lower values of AnLa were observed in the 800 m (p < 0.01) than other distances. For AnAl, the 50 m performance presented the lowest values, followed by 100 and 800 m (p < 0.01). The highest values of AnAl were observed in the 200 and 400 m (p > 0.13). The TAn was significantly higher in the 200 and 400 m performances than observed at 50 and 800 m (p < 0.01). Anaerobic contributions were correlated with 50, 100, 200, and 400 m performances (p < 0.01). The AnAl contribution was not correlated with 400 m performance. Anaerobic parameters were not correlated with 800 m performance. In conclusion, the highest values of anaerobic contribution were observed in the 200 and 400 m distances. Moreover, TAn is important to performances below 400 m, and may be used in training routines.

Physiological Acute Response to High-Intensity Intermittent and Moderate-Intensity Continuous 5 km Running Performance: Implications for Training Prescription.

The aim of this study was to investigate the physiological responses to moderate-intensity continuous and high-intensity intermittent exercise. Twelve physically active male subjects were recruited and completed a 5-km run on a treadmill in two experimental sessions in randomized order: continuously (70% sVO2max) and intermittently (1:1 min at sVO2max). Oxygen uptake, excess post-exercise oxygen consumption, lactate concentration, heart rate and rating of perceived exertion data were recorded during and after each session. The lactate levels exhibited higher values immediately post-exercise than at rest (High-Intensity: 1.43 ± 0.25 to 7.36 ± 2.78; Moderate-Intensity: 1.64 ± 1.01 to 4.05 ± 1.52 mmol⋅L-1, p = 0.0004), but High-Intensity promoted higher values (p = 0.001) than Moderate-Intensity. There was a difference across time on oxygen uptake at all moments tested in both groups (High-Intensity: 100.19 ± 8.15L; Moderate-Intensity: 88.35 ± 11.46, p < 0.001). Both exercise conditions promoted increases in excess postexercise oxygen consumption (High-Intensity: 6.61 ± 1.85 L; Moderate-Intensity: 5.32 ± 2.39 L, p < 0.005), but higher values were observed in the High-Intensity exercise protocol. High-Intensity was more effective at modifying the heart rate and rating of perceived exertion (High-Intensity: 183 ± 12.54 and 19; Moderate-Intensity: 172 ± 8.5 and 16, respectively, p < 0.05). In conclusion, over the same distance, Moderate-Intensity and High-Intensity exercise exhibited different lactate concentrations, heart rate and rating of perceived exertion. As expected, the metabolic contribution also differed, and High-Intensity induced higher energy expenditure, however, the total duration of the session may have to be taken into account. Moreover, when following moderate-intensity training, the percentage of sVO2max and the anaerobic threshold might influence exercise and training responses.

Inflammatory Cytokines and BDNF Response to High-Intensity Intermittent Exercise: Effect the Exercise Volume.

The purpose of this study was to compare the effects of two similar high-intensity intermittent exercises (HIIE) but different volume 1.25 km (HIIE1.25) and 2.5 km (HIIE2.5) on inflammatory and BDNF responses. Ten physically active male subjects (age 25.22 ± 1.74 years, body mass 78.98 ± 7.31 kg, height 1.78 ± 0.06 m, VO2peak 59.94 ± 9.38 ml·kg·min-1) performed an incremental treadmill exercise test and randomly completed two sessions of HIIE on a treadmill (1:1 min at vVO2max with passive recovery). Blood samples were collected at rest, immediately and 60-min after the exercise sessions. Serum was analyzed for glucose, lactate, IL-6, IL-10, and BDNF levels. Blood lactate concentrations was higher immediately post-exercise compared to rest (HIIE1.25: 1.69 ± 0.26-7.78 ± 2.09 mmol·L-1, and HIIE2.5: 1.89 ± 0.26-7.38 ± 2.57 mmol·L-1, p < 0.0001). Glucose concentrations did not present changes under the different conditions, however, levels were higher 60-min post-exercise than at rest only in the HIIE1.25 condition (rest: 76.80 ± 11.14-97.84 ± 24.87 mg·dL-1, p < 0.05). BDNF level increased immediately after exercise in both protocols (HIIE1.25: 9.71 ± 306-17.86 ± 8.59 ng.mL-1, and HIIE2.5: 11.83 ± 5.82-22.84 ± 10.30 ng.mL-1). Although both exercises increased IL-6, level percent between rest and immediately after exercise was higher in the HIIE2.5 than HIIE1.25 (30 and 10%; p = 0.014, respectively). Moreover, IL-10 levels percent increase between immediately and 60-min post-exercise was higher in HIIE2.5 than HIIE1.25 (37 and 10%; p = 0.012, respectively). In conclusion, both HIIE protocols with the same intensity were effective to increase BDNF and IL-6 levels immediately after exercise while only IL-10 response was related to the durantion of exercise indicanting the importance of this exercise prescription variable.

Impact of Short and Moderate Rest Intervals on the Acute Immunometabolic Response to Exhaustive Strength Exercise: Part II.

The purpose of this study was to investigate the influence of short and moderate recovery intervals during heavy strength exercise on performance, inflammatory, and metabolic responses in recreational weightlifters. Eight healthy subjects (age = 24.6 ± 4.1 years) performed 2 randomized sequences with different rest intervals: short = 90% of 1RM and 30 seconds rest allowed between sets; moderate = 90% of 1RM and 90 seconds rest allowed between sets. All sequences of exercises were performed over 4 sets until movement failure in the squat and bench press exercises, respectively. Glucose, TNF-α, IL-6, IL-10, IL-10/TNF-α ratio, and nonester fatty acid concentrations were assessed at the baseline, immediately postexercise, post-15 and post-30 minutes. We observed a statistically significant decrease after 30 seconds on maximum number of repetitions (p = 0.003) and total weight lifted (p = 0.006) after the bench press, and there was a marginal decrease in the squat (p = 0.055). The glucose concentrations showed a significant increase post-15 minutes in the 30-second condition (pre-exercise = 86.1 ± 9.1, immediately = 85.3 ± 8.2, post-15 = 97.0 ± 9.0, post-30 = 87.1 ± 5.3 mg/dl; p = 0.015); on the other hand, IL-10 increased post-30 minutes in the 90-second condition (pre-exercise = 18.2 ± 12.7, immediately = 16.4 ± 10.7, post-15 = 16.8 ± 12.2, post-30 = 35.0 ± 13.1 pg/ml; p < 0.001). In addition, the 90-second condition showed anti-inflammatory effects (as indicated by IL-10/TNF-α ratio: pre-exercise = 1.08 ± 1.32, immediately = 1.23 ± 1.20, post-15 = 1.15 ± 1.14, post-30 = 2.48 ± 2.07; p = 0.020) compared with the 30-second condition (pre-exercise = 1.30 ± 2.04, immediately = 0.99 ± 1.27, post-15 = 1.23 ± 1.82, post-30 = 1.28 ± 1.28; p = 0.635). Thus, we concluded that a moderate interval of recovery (90 seconds) during heavy strength exercise allowed higher workload, IL-10 levels, and IL-10/TNF-α ratio in recreational weightlifters.

Impact of long-term high-intensity interval and moderate-intensity continuous training on subclinical inflammation in overweight/obese adults.

Obesity is a risk factor able to trigger several inflammatory alterations and the imbalance between pro- and anti-inflammatory cytokine productions. Physical exercise is an important strategy for reduction of inflammatory established process. The aim of this study was to evaluate the effect of 16 weeks of three exercise training programs in the inflammatory profile and insulin resistance in overweight/obesity. Thirty two men and women (46.4±10.1 years; 162.0±9.1 cm; 82.0±13.6 kg) were divided into three groups for training on a treadmill: continuous at 70% maximum heart rate (HRmax) 5 times a week (CONT); 1×4 min (1-bout) and 4×4 min (high intensity interval training, HIIT) at 90% HRmax 3 times a week. Interleukin (IL) 6 and IL-10, tumor necrosis factor-alpha (TNF-α), insulin and adiponectin levels were analyzed by enzyme-linked immunosorbent assay, and homeostasis model assessment insulin resistance was calculated. After 16 weeks of training blood concentrations of IL-6 decreased in the HIIT group (P=0.035), TNF-α decreased in the CONT (P=0.037) and increased in HIIT (P=0.001) and adiponectin decreased in the three training models. There was a trend towards decreased body weight and body mass index (BMI) after HIIT only (P=0.059 and P=0.060, respectively). Despite the decrease of adiponectin and the increase of TNF-α in HIIT group, insulin sensitivity showed a trend for improvement (P=0.08). HIIT program decreased IL-6 at rest and although not significant was the only who tended to decrease total body weight and BMI. Taken together, our data suggest that both HIIT as well as CONT exercises training program promotes changes in inflammatory profile in overweight/obesity, but dissimilar response is seen in TNF-α levels.

Influence to high-intensity intermittent and moderate-intensity continuous exercise on indices of cardio-inflammatory health in men.

The aim of this study was to evaluate the influence to acute exercises performed in different intensities with volume equalized (5 km) on indices of cardio-inflammatory health. Twelve physically active male subjects (age, 23.22±5.47 years; height, 174.75±5.80 m; weight, 75.13±6.61 kg; maximal oxygen uptake, 52.92 mL/kg/min), after determination of peak oxygen uptake (VO2Peak) and the speed associated with VO2Peak (sVO2Peak), completed two randomly experimental trials: high-intensity intermittent exercise (HIIE: 1:1 at 100% sVO2Peak) and moderate-intensity continuous exercise (MICE: 70% sVO2Peak). Brain-derived neurotrophic factor (BDNF), adiponectin and plasminogen inhibitor-1 (PAI-1) data were analyzed pre, immediately, and 60 min after the exercise session. Statistical analysis comparisons between moments and between HIIE and MICE were performed using a mixed model and statistical and significance was set at <5%. PAI-1 presented an effect for time from pre to immediately after exercise moment (P<0.018) and from immediately to 60 min after exercise moment (P<0.001) only in MICE. BDNF presented an effect for time from pre to immediately after exercise to HIIE (P<0.022) and from immediately to 60 min after exercise to MICE (P<0.034). HIIE promotes BDNF increase and that there is negative correlation between PAI-1 concentrations and BDNF in both protocols in healthy sportsmen, favoring an anti-atherogenic profile.

Corrigendum: Inflammatory Cytokines and BDNF Response to High-Intensity Intermittent Exercise: Effect the Exercise Volume.

[This corrects the article on p. 509 in vol. 7, PMID: 27867360.].

Specific determination of maximal lactate steady state in soccer players.

The aim of this study was to establish the validity of the anaerobic threshold (AT) determined on the soccer-specific Hoff circuit (ATHoff) to predict the maximal lactate steady-state exercise intensity (MLSSHoff) with the ball. Sixteen soccer players (age: 16.0 ± 0.5 years; body mass: 63.7 ± 9.0 kg; and height: 169.4 ± 5.3 cm) were submitted to 5 progressive efforts (7.0-11.0 km·h) with ball dribbling. Thereafter, 11 players were submitted to 3 efforts of 30 minutes at 100, 105, and 110% of ATHoff. The ATHoff corresponded to the speed relative to 3.5 mmol·L lactate concentration. The speed relative to 4.0 mmol·L was assumed to be ATHoff4.0, and the ATHoffBI was determined through bisegmented adjustment. For comparisons, Student's t-test, intraclass correlation coefficient (ICC), and Bland and Altman analyses were used. For reproducibility, ICC, typical error, and coefficient of variation were used. No significant difference was found between AT test and retest determined using different methods. A positive correlation was observed between ATHoff and ATHoff4.0. The MLSSHoff (10.6 ± 1.3 km·h) was significantly different compared with ATHoff (10.2 ± 1.2 km·h) and ATHoffBI (9.5 ± 0.4 km·h) but did not show any difference from LAnHoff4.0 (10.7 ± 1.4 km·h). The MLSSHoff presented high ICCs with ATHoff and ATHoff4.0 (ICC = 0.94; and ICC = 0.89; p ≤ 0.05, respectively), without significant correlation with ATHoffBI. The results suggest that AT determined on the Hoff circuit is reproducible and capable of predicting MLSS. The ATHoff4.0 was the method that presented a better approximation to MLSS. Therefore, it is possible to assess submaximal physiological variables through a specific circuit performed with the ball in young soccer players.