The purpose of this systematic review and meta-analysis is to assess the effect of concurrent high intensity interval training (HIIT) and resistance training (RT) on strength and hypertrophy. Five electronic databases were searched using terms related to HIIT, RT, and concurrent training. Effect size (ES), calculated as standardised differences in the means, were used to examine the effect of concurrent HIIT and RT compared to RT alone on muscle strength and hypertrophy. Sub-analyses were performed to assess region-specific strength and hypertrophy, HIIT modality (cycling versus running), and inter-modal rest responses. Compared to RT alone, concurrent HIIT and RT led to similar changes in muscle hypertrophy and upper body strength. Concurrent HIIT and RT resulted in a lower increase in lower body strength compared to RT alone (ES = -0.248, p = 0.049). Sub analyses showed a trend for lower body strength to be negatively affected by cycling HIIT (ES = -0.377, p = 0.074) and not running (ES = -0.176, p = 0.261). Data suggests concurrent HIIT and RT does not negatively impact hypertrophy or upper body strength, and that any possible negative effect on lower body strength may be ameliorated by incorporating running based HIIT and longer inter-modal rest periods.

Relationship between Jump Test Results and Acceleration Phase of Sprint Performance in National and Regional 100m SprintersThe purpose of this research was to identify the relationship between jump test results and acceleration phase of sprint performance in national and regional 100m sprinters. Fifteen male (age 21.89 ± 3.26 years; body height 1.72.66 ± 3.20 m; body mass 61.35 ± 11.40 kg; 100 m personal best: 11.67 + 0.46 s {11.00 - 12.19}) track sprinters at a national and regional competitive level performed 10 m sprints from a block start. Anthropometric dimensions, along with squat jump (SJ), countermovement jump (CMJ), continuous straight legged jump (SLJ), single leg hop for distance, and single leg triple hop for distance measures of power were also tested. Pearson correlation analysis revealed the single leg hop for distance with front and back leg (respectively, r = -0.74 and r = -0.76; p = 0.021 and p = 0.017), and the single leg triple hop for distance with front and/or back leg (respectively, r = -0.84 and r = -0.89; p = 0.004 and p = 0.001), generated capabilities to be strongly related to sprint performance. Further linear regression analysis predicted an increase in the single leg hop for distance with front and back leg of 10 cm, to both resulted in a decrease of 0.07 s in 10 m sprint performance. Further, an increase in the single leg triple hop for distance with front and/or back leg of 10 cm was predicted to result in a 0.08 s reduction in 10 m sprint time. The results of this study seem to suggest that the ability to gain more distance with the single leg hop and the single leg triple hop for distance to be good indicators for predicting sprint performance over 10 m from a block start.

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The purpose of this study was to compare some anthropometric, body composition indexes and VO2max of Ahvaz elite soccer players of different playing positions. Material: Participants were 60 male soccer players (age 24.31±4.20 years) from 4 teams in the two highest divisions in Iran. The sample included 8 goalkeepers, 18 defenders, 20 midfielders and 14 strikers. Anthropometric variables of subjects (height, weight and BMI) and body composition (%BF) were measured. Skinfold thickness measurements were taken using Harpenden skinfold calipers at three sites (triceps, subscapular and abdominal) and the VO2max of the subjects was estimated by participation in a multi-stage 20m shuttle-run test. One-way ANOVA and Tukey testes were used for possible differences in test variables between different player positions. Results: Results revealed that the goalkeepers were significantly (p<0.05) the tallest, heaviest and had lower VO2max than another positions. Beside the midfielders had significantly (p<0.05) higher VO2max than the goalkeepers. Also, no difference in estimated body fat percentage and BMI was observed between players of all positions. Conclusion: Thus, it can be concluded that anthropometric and physiological differences are exist among soccer players who play in different positions. These differences fit with their different workload in a game. Therefore, programs must be include specific sessions for each positional role.

This study compared the effects of lower- versus higher-intensity isometric handgrip exercise on resting blood pressure (BP) and associated clinical markers in adults with hypertension. Thirty-nine males were randomly assigned to one of three groups, including isometric handgrip at 60% maximal voluntary contraction (IHG-60), isometric handgrip at 30% IHG-30, or a control group (CON) that had been instructed to continue with their current activities of daily living. The volume was equated between the exercise groups, with IHG-60 performing 8 × 30-s contractions and IHG-30 performing 4 × 2-min contractions. Training was performed three times per week for 8 weeks. Resting BP (median [IQR]), flow-mediated dilation, heart rate variability, and serum markers of inflammation and oxidative stress were measured pre- and post-intervention. Systolic BP was significantly reduced for IHG-60 (−15.5 mmHg [−18.75, −7.25]) and IHG-30 (−5.0 mmHg [−7.5, −3.5]) compared to CON (p < 0.01), but no differences were observed between both the exercise groups. A greater reduction in diastolic BP was observed for IHG-60 (−5.0 mmHg [−6.0, −4.25] compared to IHG-30 (−2.0 mmHg [−2.5, −2.0], p = 0.042), and for both exercise groups compared to CON (p < 0.05). Flow-mediated dilation increased for both exercise groups versus CON (p < 0.001). IHG-30 had greater reductions in interleukin-6 and tumor necrosis factor-α compared to the other groups (p < 0.05) and CON (p = 0.018), respectively. There was a reduction in Endothelin-1 for IHG-60 compared to CON (p = 0.018). Both the lower- and higher-intensity IHG training appear to be associated with reductions in resting BP and improvements in clinical markers of inflammation and oxidative stress.