Effects of time-of-day on neuromuscular function in untrained men: Specific responses of high morning performers and high evening performers
Küüsmaa, M., Sedliak, M., & Häkkinen, K. (2015). Effects of time-of-day on neuromuscular function in untrained men: Specific responses of high morning performers and high evening performers. Chronobiology International, 32 (8), 1115-1124. doi:10.3109/07420528.2015.1065269
Published inChronobiology International
DisciplineValmennus- ja testausoppi
© 2015 Taylor & Francis Group, LLC. This is a final draft version of an article whose final and definitive form has been published by Taylor & Francis. Published in this repository with the kind permission of the publisher.
It has been clearly established that maximal force varies during the day in human muscles but the exact mechanisms behind the diurnal rhythms are still not fully clarified. Therefore, the aim of this study was to examine the diurnal rhythms in maximal isometric force production in a large group of participants and also by separating the high morning performance types (n = 8) and the high evening performance types (n = 19) from the neutral types (n = 45) based on their actual maximal isometric force levels. Measurements were performed in the morning (7:26 h ± 63 min) and in the evening (17:57 h ± 74 min) for maximal bilateral isometric leg press force (MVCLP) together with myoelectric activity (EMGLP), maximal unilateral isometric knee extension force (MVCKE) and maximal voluntary activation level (VA%) during maximal unilateral isometric knee extension force (MVCVA) together with myoelectric activity (EMGVA). In addition, venous blood samples were drawn four times a day and serum testosterone and cortisol concentrations were analyzed. None of the participants belonged to the extreme morning or evening chronotype according to the Munich Chronotype Questionnaire. In the total group of participants, MVCLP and MVCKE were 4.4 ± 12.9% (p < 0.01) and 4.3 ± 10.6% (p < 0.01) higher in the evening compared to the morning. MVCVA and VA% did not show significant diurnal variation. The high morning performance types showed lower force values in the evening compared to the morning for MVCLP (10.8 ± 9.1%; p < 0.05) and MVCKE (5.7 ± 4.9%; p < 0.05). No significant diurnal variation was observed for MVCVA and VA%. The high evening performance types showed higher force values in the evening for MVCLP (16.1 ± 15.9%; p < 0.001), MVCKE (13.5 ± 11.3%; p < 0.001) and MVCVA (6.2 ± 9.9%; p < 0.05) with a concomitant higher VA% in the evening (p < 0.05). The neutral types showed significantly higher evening force values for the MVCLP (2.1 ± 6.7%; p < 0.05). All the other neuromuscular variables did not show significant diurnal variations. EMGLP and EMGVA did not show significant diurnal fluctuations in any group. Serum testosterone and cortisol concentrations showed normal daily rhythms with higher values observed in the morning in all of the groups (p < 0.001). Between-group differences were observed for MVCLP (p < 0.001) and MVCKE (p < 0.001) between all of the three groups. Diurnal changes in VA% differed between the high evening performance types and the neutral types (p < 0.05) and the testosterone/cortisol ratio (p < 0.05) as well as vastus lateralis EMGVA (p < 0.05) differed between the high morning and high evening performance types. In conclusion, we were able to identify the high morning performance types, the high evening performance types and the neutral types who showed significantly different diurnal rhythms in force production, irrespective of their actual chronotype. Therefore, the questionnaires designed to determine the chronotype may not always be sensitive enough to determine the “morningness” or “eveningness” in maximal neuromuscular performance. In general, central factors could partially explain the diurnal fluctuations in maximal strength performance, but peripheral mechanisms were also possibly involved. ...
PublisherTaylor & Francis; International Society for Chronobiology
MetadataShow full item record
- Liikuntatieteiden tiedekunta 
Showing items with similar title or keywords.
Acute neuromuscular and endocrine responses and recovery to single session combined endurance and strength loadings: ‘Order effect’ in untrained young men. Schumann, Moritz; Eklund, Daniela; Taipale, Ritva; Nyman, Kai; Kraemer, William J; Häkkinen, Arja; Izquierdo, Mikel; Häkkinen, Keijo (Lippincott Williams & Wilkins, 2013)The purpose of this study was to investigate acute neuromuscular and endocrine responses and recovery to a single session of combined endurance and strength loading using two loading orders. Forty-two men were demographically ...
Concurrent endurance and strength training : neuromuscular, cardiorespiratory and hormonal effects of the exercise order in previously untrained and recreationally endurance trained men Schumann, Moritz (University of Jyväskylä, 2015)The aim of the present thesis was two-fold. First, to investigate physiological adaptations to concurrent endurance and strength training performed in the same session with different exercise orders (i.e. commencing ...
Effects of 11-week volume-equated hypertrophic strength training performed at workplace in one or two sessions on isometric strength and muscle CSA in untrained men Hietanen, Pauliina (2020)Background. As the recommended amount of weekly resistance training tends to fall short, introducing low-threshold options for resistance training incorporated within working day could turn out beneficial. Consensus exists ...
Sympathoadrenal response to resistance exercise in men, women and pubescent boys : with special reference to interaction with other hormones and neuromuscular performance Pullinen, Teemu (University of Jyväskylä, 2001)
Combined Strength and Endurance Training: Effect of Training Order and Time-of-Day on Adaptations in Neuromuscular and Cardiorespiratory Performance, Muscle Hypertrophy, Serum Hormone Concentrations and Wellbeing Küüsmaa-Schildt, Maria (2019)The aim of this study was to assess the daily fluctuations in strength and endurance performance and to examine chronic adaptations to time-of-dayspecific same-session combined strength (S) and endurance (E) training ...