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.

The aim of this study was to compare heart rate variability (HRV) recovery after 2 sessions of high-intensity intermittent exercise at different volumes (1.25 km [HIIE] and 2.5 km [HIIE]). 13 participants determined their maximal aerobic speed (MAS) and completed 2 HIIE (1:1 at 100% MAS) trials. The heart rate was recorded before and after each session. HRV indicators were calculated according to time (RMSSD and SDNN) and frequency (LF, HF and LF/HF ratio) domains. SDNN and RMSSD presented effect of test (F=20.97; p<0.01 and F=21.00; p<0.01, respectively) and moment (F=6.76; p<0.01 and F=12.30; p<0.01, respectively), without interaction. Even though we did not find an interaction effect for any HRV variables, the HIIE presented a delay of only 5 min in HRV recovery, when compared to HIIE. However, the effects of the test (SDNN, RMSSD, LF-log, and HF-log) indicate higher autonomic stress during the entire recovery period. These findings may indicate that exercise volume interferes with HRV recovery. If so, physically active subjects may choose a lower volume exercise (i. e., HIIE) in order to promote similar physical fitness adaptations with lower loading on autonomic modulation.

In the "Abstract" Section, there was a mistake in the BDNF-values of the HIIE1.25, once the values of the standard deviation were spliced and did not contain the comma. HIIE1.25: 9.71 ± 306 is incorrect, the correct value is HIIE1.25: 9.71 ± 3.06.In the last sentence of the "Abstract", the word "duration" was misspelled as "durantion".In the "Results" Section, the last word of the first paragraph there is an error in spelling the word duration, appears as duation.Finally, in the "Discussion" Section, the last sentence of the fourth paragraph has been modified from: "However, after 60-min, the IL-10 levels had returned to baseline values in both protocols." to "However, after 60-min, the IL-10 levels had returned to baseline values only in HIIE1.25 km protocol."The authors apologize for these errors. These do not change the scientific conclusions of the article in any way.

No abstract

Os treinamentos aeróbio intervalado e resistido são utilizados na prevenção e tratamento da Síndrome Metabólica (SMet), porém há lacunas quanto às diferentes metodologias aplicadas. O objetivo foi analisar e comparar o comportamento da pressão arterial após treinamentos periodizado aeróbio e resistido em adultos com Síndrome Metabólica. Vinte e nove voluntários, sedentários de ambos os sexos, com idade entre 35 e 60 anos com SMet, foram aleatorizados em 3 grupos: treinamento aeróbio intervalado (TAI; n=9), treinamento resistido (TRC; n=11) e o grupo controle (n=9). O programa foi constituído por 3 sessões semanais durante 12 semanas. Antes e após o treinamento foi mensurada a pressão arterial em repouso. Houve diminuição da pressão arterial sistólica de 7mmHg no grupo TAI, sem significância estatística. Não foram observadas alterações na pressão arterial diastólica. Após ambos treinamentos periodizados não foram observados mudanças na pressão arterial em participantes com SMet. Palavras-chave: Síndrome metabólica, pressão arterial, treinamento de resistência, exercício.