ArticlePDF AvailableLiterature Review

Morning and evening exercise

December 2013
Integrative Medicine Research

DOI:10.1016/j.imr.2013.10.003

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A growing body of evidence suggests that exercise may contribute to preventing pathological changes, treating multiple chronic diseases, and reducing mortality and morbidity ratios. Scientific evidence moreover shows that exercise plays a key role in improving health-related physical fitness components and hormone function. Regular exercise training is one of the few strategies that has been strictly adapted in healthy individuals and in athletes. However, time-dependent exercise has different outcomes, based on the exercise type, dura-tion, and hormone adaptation. In the present review, we therefore briefly describe the type, duration, and adaptation of exercise performed in the morning and evening. In addition, we discuss the clinical considerations and indications for exercise training.

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integr med res 2 (2013) 139–144

Available online at www.sciencedirect.com

Integrative Medicine Research

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Review Article

Morning and evening exercise

Dae Yun Seoa, SungRyul Leea, Nari Kim a, Kyung Soo Koa,

Byoung Doo Rheea, Byung Joo Parkb, Jin Hana,∗

aNational Research Laboratory for Mitochondrial Signaling, Department of Physiology, College of Medicine,

Cardiovascular and Metabolic Disease Center, Inje University, Busan, Korea

bDivision of Leisure and Sports Science, Dong Seo University, Busan, Korea

article info

Article history:

Received 6 September 2013

Received in revised form

4 October 2013

Accepted 4 October 2013

Available online 14 October 2013

Keywords:

circadian rhythm

evening exercise

hormone

morning exercise

abstract

A growing body of evidence suggests that exercise may contribute to preventing patho-

logical changes, treating multiple chronic diseases, and reducing mortality and morbidity

ratios. Scientiﬁc evidence moreovershows that exercise plays a key role in improving health-

related physical ﬁtness components and hormone function. Regular exercise training is one

of the few strategies that has been strictly adapted in healthy individuals and in athletes.

However, time-dependent exercise has different outcomes, based on the exercisetype, dura-

tion, and hormone adaptation. In the present review, we therefore brieﬂy describe the type,

duration, and adaptation of exercise performed in the morning and evening. In addition, we

discuss the clinical considerations and indications for exercise training.

article under the CC BY-NC-ND license

(http://creativecommons.org/licenses/by-nc-nd/4.0/).

1. Introduction

Increased muscle strength and cardiac ﬁtness reﬂect regular

physical activity.1–3 This reﬂection is strongly associated with

time-dependent exercise.4,5 Recent studies have attempted to

elucidate the manner in which different exercise types and

duration are involved in the regulation of several physiological

responses through morning and evening exercise because this

information is important in improving muscle ﬁtness, aerobic

capacity, and well-being.5–8

The beneﬁcial effect obtained from exercise is gener-

ally determined by multiple systems such as the motor,

physiological, and neurobiological systems.9–11 In particular,

physiological and neurobiological activities are dependent on

biological rhythms in the human body; this is also known

∗Corresponding author. National Research Laboratory for Mitochondrial Signaling, Department of Physiology, College of Medicine, Car-

diovascular and Metabolic Disease Center, Inje University, 633-165 Gaegeum-Dong, Busanjin-Gu, Busan 614-735, Korea.

E-mail address: phyhanj@inje.ac.kr (J. Han).

as circadian or diurnal rhythms.12–15 This phenomenon has

been widely described in time-of-day studies. Despite the fact

that the data in the literature have shown a signiﬁcant asso-

ciation between time and aerobic exercise,16–18 other studies

have not indicated any such circadian variations.19–21 These

results indicate that the time-course effects of aerobic exer-

cise on maximal aerobic velocity and exhaustion time remain

unclear.11,14 Other reports have described the use of time-of-

day for resistance exercise.22–24 The results of time variations

during resistance exercise (which involve muscle strength,

power, and sprint) range from 3% to 21.2%, depending on the

individual being tested, the position of the muscles, and the

experimental design.25,26

The warm-up duration, sleep deprivation, and training

time prior to exercise training can be affected by diurnal

variation.27,28 Sedliak et al29 report that exercise performed in

http://dx.doi.org/10.1016/j.imr.2013.10.003

(http://creativecommons.org/licenses/by-nc-nd/4.0/).

140 Integr Med Res (2013) 139–144

the morning can improve muscle strength. However, another

study obtained contradicting results and showed that par-

ticipants were able to perform more physical activity in the

evening, despite the lower physiological variation at this

time.30 However, variations in the neuromuscular perfor-

mance level increased during evening exercise. Thus, further

information on the differences in the effects of morning and

evening exercises is required. In this review, we discuss the

exercise effects on aerobic and anaerobic performance, on

short and long duration, and on hormone adaptation through

time-of-day exercise studies.

2. Differential effect of exercise type

2.1. Aerobic training

In general, aerobic exercise plays a role in weight loss

management,31 and improves peak maximal oxygen con-

sumption (VO2max)32 and workload.33 Several studies have

recently conﬁrmed the presence of time-of-day effects of exer-

cise on these variables.34,35 Therefore, health and disease

outcomes in response to exercise may depend on the time

of day the exercise is performed.36,37 Hobson et al38 suggest

the existence of a time-of-day effect on aerobic exercise for

improving aerobic exercise capacity. The authors observed

that the endurance exercise capacity of men during exhaus-

tive cycling exercise at 65% peak VO2was signiﬁcantly greater

in the morning than in the evening. In addition, Shiotani et

al30 found that a two-month aerobic exercise program, which

consisted of ergometer cycling, increased the heart rate in the

morning. However, another study found that an evening exer-

cise training group had a greater work capacity after 5 weeks

of high-intensity training, compared to the morning exercise

training group.39 Faisal et al40 similarly indicated the presence

of a time-of-day speciﬁcity on the effects of aerobic exercise

training. Therefore, the studies in the literature indicate that

different effects may be elicited, depending on the exercise

duration, time, and the individual.

2.2. Resistance training

Resistance exercise elicits improved muscle strength and

power, and elicits changes in anabolism/catabolism, depend-

ing on the time of the day.41,42 Souissi et al43 found that,

compared to evening exercise, morning exercise yielded

more beneﬁcial effects on anaerobic performance after 6

weeks of resistance training. After examining study partic-

ipants who underwent resistance training for 6 weeks in

the morning, Chtourou et al27 similarly noted that muscle

performance—determined by the one-repetition, squat jump,

and Wingate tests—was signiﬁcantly higher among this group

than among individuals who performed resistance training in

the evening. By contrast, certain researchers have reported

that evening exercise is more effective than morning exer-

cise, and one study showed a signiﬁcant improvement in peak

muscle power in well-trained cyclists in the evening than in

the morning.44 Furthermore, Edwards et al45 showed that grip

strength, isokinetic knee ﬂexion, peak power, and peak torque

were higher in the evening than in the morning.

However, Sedliak et al46,47 observed that after 10 weeks of

exercise in a diurnal pattern the maximum isometric strength

was not altered in the morning and evening. In a similar study,

some researchers indicated that no time-of-day changes were

observed in muscular anaerobic performance. Chtourou et al48

measured electromyography (EMG) activity in study partici-

pants performing the 30-second Wingate test in the morning

and evening; however, the authors did not note any signiﬁ-

cant differences in EMG activity during the entire 30seconds

between the morning and evening exercise. In another study,

Chtourou et al27 similarly indicated that, after 8 weeks of

lower extremity progressive resistance training, the muscle

strength was similar between the participants who performed

the exercise in the morning and participants who performed

the exercise in the evening. Sedliak et al47 did not show any

time-of-day-speciﬁc adaptations during unilateral isometric

knee extension peak torque training. Zarrouk et al49 inves-

tigated the time-of-day effects on repeated sprint ability, but

did not observe any signiﬁcant time-of-day effects on the EMG

activity levels of four thigh muscles during a repeated ped-

aling sprint exercise. Chtourou et al50 moreover showed no

signiﬁcant difference in muscular power or strength between

the morning and evening tests. To understand better the

time-of-day effects on muscle strength responses, future stud-

ies should assess the main physiological variations following

resistance exercise adaptations.

2.3. Differential effect of exercise duration

Many scientists have investigated different exercise types,

times, durations, and intensities of exercise training. Exercise

duration is particularly important. Many studies have shown

that short-term performance changes with different exer-

cise times. In addition, short-term exercise training, which

enhances anabolic metabolism, can be inﬂuenced by several

factors such as time-of-day training.47,51 In previous stud-

ies, exercise training improved anaerobic performance in the

morning and/or evening29,46 (Table 1). Most investigations

have shown that evening exercise is better than morning

exercise.27,47,50,52 Souissi et al43 indicated that 6 weeks of resis-

tance training in 10-year-old and 11-year-old boys improved

muscle strength and power to a signiﬁcantly greater extent in

the evening than in the morning. Brisswalter et al53 investi-

gated the effects of moderate exercise and determined that

VO2kinetics were signiﬁcantly higher in the morning than in

the evening. Souissi et al28 observed the effect of different

exercise training times on anaerobic performance, includ-

ing peak anaerobic power, jump performance, and peak knee

extension toque. Their study found that the group that was

trained in the evening had greater improvements in anaerobic

performance. Lricollais et al54 moreover showed that, during

the 60 second Wingate test, muscle fatigue was lower in the

evening than in the morning.

Long-term exercise has beneﬁcial effects on aerobic capac-

ity, cardiac function, and rehabilitation. In particular, this type

of exercise is important in exercises involving time trials such

as cycling, rowing, swimming, running, football, and table ten-

nis. In a previous study, Deschenes et al21 observed that during

aerobic exercise, the mean arterial blood pressure was higher

D.Y. Seo et al/Morning and evening exercise 141

Table1–Theeffect of time of day on short-term exercises.

Refs Participants Age (y) Measurement parameters Acrophase Amplitude

Atkinson et al69 Trained (n=7)

Untrained (n=7)

19–29

Trained, 23.9 ±3.3

Untrained, 24.3 ±24

Whole-body ﬂexibility

Back and leg strength

Grip strength

Flight time in a vertical

jump

Self-chosen work rate

17:00–19:00 h Trained > untrained

(∼2–10% vs. ∼1–7%)

Wyse et al70 9 Collegiate

sportsmen

19.6 ±9.6 Extension peak torque

Flexion peak torque

18.00–19.30 h ∼5–12%

Gauthier et al52 13 Physical

education

participants

M: 22.0 ±: 22.0

physical education

Elbow ﬂexor torque 18:00 h ∼4%

Martin et al71 13 Healthy

participants

(12 M and 1 F)

22–40 MVC 18:00 h 8.9%

Callared et al72 6M

ultradistance

cyclists

33.4 ±3.4 MVC 19:30 h 6%

Souissi et al73 13 M physical

education

students

22.4 ±2.4 Maximal power during

the force velocity test

18:00 h 8.3%

Castaingts et al74 11 M 18–30 MVC 18:00 h 8.6%

F, female; M, male; MVC, maximal voluntary contraction; NS, not signiﬁcant.

Note. From “The effect of training at a speciﬁc time of day: a review”, by H. Chtourou and N. Souissi, 2012, J Strength Cond Res,26, p.1984–2005.

in the morning than in the evening (Table 2). In agreement

with these studies, Edwards et al55 investigated the effect of

submaximal cycling at 60% of VO2max, and found that the

morning exercise group exhibited greater improvements in

lactate levels, compared to the evening exercise group.43 By

contrast, Reilly and Garrett19 indicated a higher power out-

put during a 60-minute cycle ergometer test in the evening

than in the morning. Atkinson and Reilly13 also indicated that,

after a 1.6-km time trail exercise, the heart rate and blood

lactate levels exhibited greater improvements in the evening

exercise group than in the morning exercise group. However,

previous studies did not indicate any difference in the time-of-

day effect on exhaustion during maximal19,21 and submaximal

cycling.55

2.4. Hormone adaptation

The role of adrenal steroids in response to exercise train-

ing is very important for improving muscle cell and protein

synthesis.56–58 Many researchers have revealed different time-

of-day effects of anabolic hormones (such as testosterone

and cortisol) on muscle strength and protein synthesis within

skeletal muscle.6,59,60 Testosterone is a male sex hormone and

its anabolic effects are observed during male adolescence and

adulthood.61 During exercise training and physical activity,

the main effect of testosterone is on insulin sensitivity and

on the maintenance of muscle protein synthesis within the

muscular system.62,63

Cortisol is catabolic in nature, and is a stress hormone.64

Florini65 found that cortisol exerts catabolic effects on

muscle tissue. Increased cortisol levels may also inhibit

protein synthesis.66 Testosterone and cortisol both exhibit

diurnal variations in peak concentrations in the morn-

ing and/or evening.67 Florini65 observed increased cortisol

levels in the morning, which may stimulate an increase

in glucogenesis, proteolytic activity, and skeletal protein

turnover.59 This effect may generate the catabolic sta-

tus of muscle tissue. Increased testosterone levels may

Table2–Theeffect of time of day on longterm exercises.

Refs Participants Age (y) Measurement parameters Acrophase

Dalton et al20 7 M competitive cyclists

or triathletes

22.3 ±2.3 Total work during a timed trial cycling

performance of 15-min duration

Average power output during a time trial cycling

performance of 15 min duration

Bessot et al72,75 10 M competitive

endurance cyclists

21.5 ±1.5 Free pedal rate during 4 ×5min cycling exercise NS

Edwardsetal

55 8 M recreational cyclists 24.3 ±4 Work rate during 30-min submaximal cycling at

60% of VO2max

M, male; NS, not signiﬁcant; VO2max, maximal oxygen consumption.

Note. From “The effect of training at a speciﬁc time of day: a review”, by H. Chtourou and N. Souissi, 2012, J Strength Cond Res,26, p. 1984–2005.

142 Integr Med Res (2013) 139–144

furthermore offset the effects of cortisol on skeletal protein

degradation.68

Several investigators have indicated that hormonal

responses can be inﬂuenced by the time of exercise training

and the intensity, and duration of exercise. Sedliak et al29

indicated that testosterone levels did not change in response

to resistance training in the morning. Another study showed

that 10 weeks of training did not induce any signiﬁcant

differences in testosterone and cortisol levels.24 Deschenes et

al21 also report that resistance exercise has no effect on the

diurnal variations in cortisol and testosterone levels. However,

Bird and Tarpenning23 showed that cortisol levels were lower

in the evening than in the morning. These results suggest

that the skeletal muscle metabolism may be improved at

that time of the day. However, further research is required

to support the use of different exercise timings, based on

hormonal responses.

3. Limitations

The present study indicates the defenses in the time-of-day

effects of exercise, exercise type, exercise duration, and hor-

mone adaptation among healthy individuals. However, we did

not assess the beneﬁcial time-of-day effect in patients with a

chronic disease. Therefore, if further studies assess the bene-

ﬁcial time-of-day effect in patients with chronic disease, such

studies should carefully consider only the results of physio-

logical variation.

4. Conclusions

The literature contains more than 70 different exercise types,

times, and hormonal adaptations. In the present review, we

conﬁrm that the diurnal or hormone variations lead to dif-

ferences in physical performance, depending on the time of

the day. In addition, the results indicate differences in phys-

ical performance for exercise performed in the morning and

evening, thus suggesting that these factors should be consid-

ered by scientists, coaches, and athletes.

Conﬂicts of interest

All authors have no conﬂicts of interest to declare.

Acknowledgment

This work was supported by the 2005 Inje University research

grant.

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Does the time of day differently impact the effects of an exercise program on postural control in older subjects? A pilot study

Article

Full-text available

Apr 2022

Background: The time of day that people exercise can potentially influence the efficiency of exercises for fall prevention in older adults. The present pilot study was conducted to explore the feasibility and effects of morning versus afternoon exercising on postural control in institutionalized older adults. Methods: Nine older adults completed a 3-month multimodal exercise program in its entirety (14 participants were recruited at the beginning and were initially randomly separated into two groups). One group exercised in the morning (ME; n = 4) and the other in the afternoon (AE; n = 5). Postural control was assessed with a force platform at pre and post-intervention at the following times: 8 a.m., 11 a.m., 2 p.m. and 5 p.m. Results: Postural control significantly improved only in the AE group post-intervention. Improvements in postural control in the AE group were mainly observed in the morning. Conclusions: The afternoon would be the best period to implement exercise sessions dedicated to improve postural control in older subjects with benefits mainly observed in the morning. Further studies are needed with a larger sample in order to confirm these results.

Best Time of Day for Strength and Endurance Training to Improve Health and Performance? A Systematic Review with Meta-analysis

Article

Full-text available

May 2023

Background Current recommendations for physical exercise include information about the frequency, intensity, type, and duration of exercise. However, to date, there are no recommendations on what time of day one should exercise. The aim was to perform a systematic review with meta-analysis to investigate if the time of day of exercise training in intervention studies influences the degree of improvements in physical performance or health-related outcomes. Methods The databases EMBASE, PubMed, Cochrane Library, and SPORTDiscus were searched from inception to January 2023. Eligibility criteria were that the studies conducted structured endurance and/or strength training with a minimum of two exercise sessions per week for at least 2 weeks and compared exercise training between at least two different times of the day using a randomized crossover or parallel group design. Results From 14,125 screened articles, 26 articles were included in the systematic review of which seven were also included in the meta-analyses. Both the qualitative synthesis and the quantitative synthesis (i.e., meta-analysis) provide little evidence for or against the hypothesis that training at a specific time of day leads to more improvements in performance-related or health-related outcomes compared to other times. There was some evidence that there is a benefit when training and testing occur at the same time of day, mainly for performance-related outcomes. Overall, the risk of bias in most studies was high. Conclusions The current state of research provides evidence neither for nor against a specific time of the day being more beneficial, but provides evidence for larger effects when there is congruency between training and testing times. This review provides recommendations to improve the design and execution of future studies on this topic. Registration: PROSPERO (CRD42021246468).

Morning Exercise Reduces Abdominal Fat and Blood Pressure in Women; Evening Exercise Increases Muscular Performance in Women and Lowers Blood Pressure in Men

Article

Full-text available

May 2022

The ideal exercise time of day (ETOD) remains elusive regarding simultaneous effects on health and performance outcomes, especially in women. Purpose: Given known sex differences in response to exercise training, this study quantified health and performance outcomes in separate cohorts of women and men adhering to different ETOD. Methods: Thirty exercise-trained women (BMI = 24 ± 3 kg/m ² ; 42 ± 8 years) and twenty-six men (BMI = 25.5 ± 3 kg/m ² ; 45 ± 8 years) were randomized to multimodal ETOD in the morning (0600–0800 h, AM) or evening (1830–2030 h, PM) for 12 weeks and analyzed as separate cohorts. Baseline (week 0) and post (week 12) muscular strength (1-RM bench/leg press), endurance (sit-ups/push-ups) and power (squat jumps, SJ; bench throws, BT), body composition (iDXA; fat mass, FM; abdominal fat, Abfat), systolic/diastolic blood pressure (BP), respiratory exchange ratio (RER), profile of mood states (POMS), and dietary intake were assessed. Results: Twenty-seven women and twenty men completed the 12-week intervention. No differences at baseline existed between groups (AM vs PM) for both women and men cohorts. In women, significant interactions ( p < 0.05) existed for 1RM bench (8 ± 2 vs 12 ± 2, ∆kg), pushups (9 ± 1 vs 13 ± 2, ∆reps), BT (10 ± 6 vs 45 ± 28, ∆watts), SJ (135 ± 6 vs 39 ± 8, ∆watts), fat mass (−1.0 ± 0.2 vs −0.3 ± 0.2, ∆kg), Abfat (−2.6 ± 0.3 vs −0.9 ± 0.5, ∆kg), diastolic (−10 ± 1 vs−5 ± 5, ∆mmHg) and systolic (−12.5 ± 2.7 vs 2.3 ± 3, mmHg) BP, AM vs PM, respectively. In men, significant interactions ( p < 0.05) existed for systolic BP (−3.5 ± 2.6 vs −14.9 ± 5.1, ∆mmHg), RER (−0.01 ± 0.01 vs −0.06 ± 0.01, ∆VCO 2 /VO 2 ), and fatigue (−0.8 ± 2 vs −5.9 ± 2, ∆mm), AM vs PM, respectively. Macronutrient intake was similar among AM and PM groups. Conclusion: Morning exercise (AM) reduced abdominal fat and blood pressure and evening exercise (PM) enhanced muscular performance in the women cohort. In the men cohort, PM increased fat oxidation and reduced systolic BP and fatigue. Thus, ETOD may be important to optimize individual exercise-induced health and performance outcomes in physically active individuals and may be independent of macronutrient intake.

Nrf2 modulates the benefits of evening exercise in type 2 diabetes

Article

Full-text available

Sep 2023

Exercise has well-characterized therapeutic benefits in the management of type 2 diabetes mellitus (T2DM). Most of the beneficial effects of exercise arise from the impact of nuclear factor erythroid 2 related factor-2 (Nrf2) activation of glucose metabolism. Nrf2 is an essential controller of cellular anti-oxidative capacity and circadian rhythms. The circadian rhythm of Nrf2 is influenced by circadian genes on its expression, where the timing of exercise effects the activation of Nrf2 and the rhythmicity of Nrf2 and signaling, such that the timing of exercise has differential physiological effects. Exercise in the evening has beneficial effects on diabetes management, such as lowering of blood glucose and weight. The mechanisms responsible for these effects have not yet been associated with the influence of exercise on the circadian rhythm of Nrf2 activity. A better understanding of exercise-induced Nrf2 activation on Nrf2 rhythm and signaling can improve our appreciation of the distinct effects of morning and evening exercise. This review hypothesizes that activation of Nrf2 by exercise in the morning, when Nrf2 level is already at high levels, leads to hyperactivation and decrease in Nrf2 signaling, while activation of Nrf2 in the evening, when Nrf2 levels are at nadir levels, improves Nrf2 signaling and lowers blood glucose levels and increases fatty acid oxidation. Exploring the effects of Nrf2 activators on rhythmic signaling could also provide valuable insights into the optimal timing of their application, while also holding promise for timed treatment of type 2 diabetes.

Comparison of the effects of the time of home-based cardiac rehabilitation program on the changes in cardiometabolic risk factors in patients with phase-IV myocardial infarction: A randomized controlled trial

Article

Full-text available

Jan 2022

Background: It seems that the time of performing cardiac rehabilitation is important in determining the risk of cardiac complications in patients with myocardial infarction (MI). The present study aimed to investigate the effects of a home-based cardiac rehabilitation program (HCRP) conducted in either the morning or evening on cardiometabolic risk factors in phase IV (maintenance) MI patients. Methods: In this randomized controlled clinical trial, 80 patients with MI were divided into 2 groups of intervention and control (40 individuals per group). Patients in each group were categorized into morning and evening subgroups (20 individuals per subgroup). The therapeutic regimen in the intervention group included HCRP, routine medications, and exercise and walking programs for 8 weeks. Patients in the control group received routine treatments for 8 weeks. Cardiovascular risk factors comprising of cardiac troponin I (cTnI), mean platelet volume (MPV), C-reactive protein (CRP), and cardiometabolic indicators including cholesterol (Cho), high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglyceride (TG), and the maximum rate of oxygen consumption (VO2 max) were measured for all patients before and after the intervention. Results: Our results showed significant reductions in Cho, TG, HDL, LDL, VO2 max, CRP, and MPV (P < 0.05) in the group performing HCRP in the evening compared with the morning group. Conclusion: Performing HCRP in the evening, compared with morning, can be significantly more effective in improving the levels of cardiometabolic risk factors in patients with MI. Therefore, it is recommended that rehabilitation programs be implemented in these patients in evening shifts.

Pengaruh Gerakan Shalat Dhuha 4 Rakaat Terhadap Fleksibilitas Otot Punggung Bawah Mahasiswa Pesantren Abu Dzar Al-Ghifari Malang

Article

Full-text available

Dec 2022

Mahasiswa disibukkan dengan berbagai kegiatan perkuliahan ditambah kebiasaan duduk pada posisi yang salah dan terlalu lama dapat menyebabkan fleksibilitas menurun. Salah satu cara untuk meningkatkan serta mempertahankan fleksibilitas otot punggung bawah adalah dengan gerakan rukuk yang benar dan tepat pada shalat dhuha 4 rakaat. Pada saat gerakan rukuk dilakukan otot tipe I, mengalami kontraksi berulang dan resistensi minimal karena tarikan gravitasi bumi. Penelitian ini mendeskripsikan pengaruh gerakan rukuk pada shalat dhuha 4 rakaat terhadap fleksibilitas otot punggung bawah pada mahasiswa Pesantren Abu Dzar Al-Ghifari Malang. Desain penelitian ini adalah pre-experimental, yaitu One Group Pre-Test and Post-Test Design pada 30 mahasiswa yang mengalami penurunan fleksibilitas dengan alat ukur Sit Up and Reach Test. Berdasarkan hasil uji Paired Sample T Test di dapatkan hasil yang siginifikan yaitu 0,000, dinyatakan bahwa terdapat pengaruh gerakan rukuk pada shalat dhuha 4 rakaat terhadapa fleksibilitas otot punggung bawah responden. Maka disimpulkan gerakan rukuk pada shalat dhuha 4 rakaat selama 15 hari memberikan pengaruh pada fleksibilitas otot punggung bawah mahasiswa Pesantren Abu Dzar Al-Ghifari Malang.

Eastward Jet Lag is Associated with Impaired Performance and Game Outcome in the National Basketball Association

Article

Full-text available

Jun 2022

Objectives: Elite athletes are often required to travel across time zones for national and international competitions, causing frequent jet lag. The aim of this study was to examine whether the direction of travel-related jet lag is associated with performance in the National Basketball Association (NBA), and if so, to explore potential mechanisms. Methods: Ten seasons comprising of 11,481 games of NBA data from the 2011/2012 to the 2020/2021 regular season were analyzed using multi-level mixed models with one fixed factor (three levels; jet lag direction: eastward vs westward vs no jet lag) and three random factors (team, opponent, game time). Predicted circadian resynchronization rate was accounted for, and home and away games were analysed separately. Mediation analyses were performed to examine potential mechanisms. Results: Among home teams, eastward (but not westward) jet lag was associated with reduced winning (Δ (i.e., change) = −6.03%, p = 0.051, marginal), points differential (Δ = −1.29 points, p = 0.015), rebound differential (Δ = −1.29 rebounds, p < 0.0001), and effective field goal percentage differential (Δ = −1.2%, p < 0.01). As the magnitude of eastward jet lag increased, home team points differential decreased (2 h Δ = −4.53 points, p < 0 . 05; 1 h Δ = −0.72 points, p = 0.07). No significant associations were found between jet lag and away team performance. Conclusion: Eastward jet lag was associated with impaired performance for home (but not away) teams. Sleep and circadian disruption associated with advancing phase following eastward travel may have significant adverse consequences on performance in the NBA, particularly when recovery time is limited. Sports organisations could consider chronobiology-informed scheduling and interventions to maximise recovery and performance of their athletes.

Article

Jan 2022

BACKGROUND: It seems that the time of performing cardiac rehabilitation is important in determining the risk of cardiac complications in patients with myocardial infarction (MI). The present study aimed to investigate the effects of a home-based cardiac rehabilitation program (HCRP) conducted in either the morning or evening on cardiometabolic risk factors in phase IV (maintenance) MI patients.

The Cardiac Circadian Clock

Article

Jun 2023

Martin E Young

Aerobic and resistance exercises affect the BDNF/TrkB signaling pathway, and hippocampal neuron density of high-fat diet-induced obese elderly rats

Article

Mar 2023
PHYSIOL BEHAV

Obesity, caused by a high-fat diet (HFD) in elderly, is a risk factor for insulin resistance and a precursor to diabetes and can lead to impaired cognitive function. Physical exercise has positive effects on decrease obesity and improvement brain function. We investigated which type of aerobic (AE) or resistance (RE) exercise can be more effective in reducing HFD-induced cognitive dysfunction in obese elderly rats. 48 male Wistar rats (19-monthold) were divided into six groups: Healthy control (CON), CON+AE, CON+RE, HFD, HFD+AE, and HFD+RE. Obesity was induced by 5 months of HFD feeding in older rats. After obesity confirmation, RT (with a range of 50% to 100%1RM/3 days/week) and AE (running at 8-m/min for 15-min to 26-m/min for 60-min /5 days/week) was performed for 12-weeks. Morris water maze Test was used to evaluate cognitive performance. All data were analyzed using two-way statistical test of variance. The results showed that obesity had a negative effect on glycemic index, increased inflammation, decreased antioxidant levels, decreased BDNF/TrkB and decreased nerve density in hippocampal tissue. The Morris water maze results clearly showed cognitive impairment in the obesity group. But 12 weeks after AE and RE, all the measured variables were on the improvement path, and in general, no difference was observed between the two exercise methods. Two mods of exercise (AE and RE) may be having same effects on nerve cell density, inflammatory, antioxidant and functional status of hippocampus of obese rats. Each of the AE and RE can create beneficial effects on the cognitive function of the elderly.

Time of Day Effects on Repeated Sprint Ability

Data

Full-text available

Jul 2012

Does lowering evening rectal temperature to morning levels offset the diurnal variation in muscle force production?

Article

Full-text available

Jul 2013

Muscle force production and power output in active males, regardless of the site of measurement (hand, leg, or back), are higher in the evening than the morning. This diurnal variation is attributed to motivational, peripheral, and central factors and higher core and, possibly, muscle temperatures in the evening. This study investigated whether decreasing evening resting rectal temperatures to morning values, by immersion in a water tank, leads to muscle force production and power output becoming equal to morning values in motivated subjects. Ten healthy active males (mean ± SD: age, 22.5 ± 1.3 yrs; body mass, 80.1 ± 7.8 kg; height, 1.72 ± 0.05 m) completed the study, which was approved by the local ethics committee of the university. The subjects were familiarized with the techniques and protocol and then completed three sessions (separated by at least 48 h): control morning (07:30 h) and evening (17:30 h) sessions (with an active 5-min warm-up on a cycle ergometer at 150 W) and then a further session at 17:30 h but preceded by an immersion in cold water (~16.5 °C) to lower rectal temperature (Trec) to morning values. During each trial, three measures of grip strength, isokinetic leg strength measurements (of knee flexion and extension at 1.05 and 4.19 rad s(-1) through a 90° range of motion), and three measures of maximal voluntary contraction (MVC) on an isometric dynamometer (utilizing the twitch-interpolation technique) were performed. Trec, rating of perceived exertion (RPE), and thermal comfort (TC) were also measured after the subjects had reclined for 30 min at the start of the protocol and prior to the measures for grip, isokinetic, and isometric dynamometry. Muscle temperature was taken after the warm-up or water immersion and immediately before the isokinetic and MVC measurements. Data were analyzed using general linear models with repeated measures. Trec values were higher at rest in the evening (by 0.37 °C; p < 0.05) than the morning, but values were no different from morning values immediately after the passive pre-cooling. However, Trec progressively decreased throughout the experiments, this being reflected in the subjects' ratings of thermal comfort. Muscle temperatures also displayed significant diurnal variation, with higher values in the evening (by 0.39 °C; p < 0.05). Right grip strength, isometric peak power, isokinetic knee flexion and extension for peak torque and peak power at 1.05 rad s(-1), and knee extension for peak torque at 4.19 rad s(-1) all showed higher values in the evening (a range of 3-14%), and all other measures of strength or power showed a statistical trend to be higher in the evening (0.10 > p > 0.05). Pre-cooling in the evening significantly reduced force or power variables towards morning values. In summary, effects of time of day were seen in some measures of muscle performance, in agreement with past research. However, in this population of motivated subjects, there was evidence that decreasing evening Trec to morning values by coldwater immersion decreased muscle strength to values similar to those found in the morning. It is concluded that diurnal changes in muscle performance are linked to diurnal changes in Trec.

Muscle, Prefrontal, and Motor Cortex Oxygenation Profiles During Prolonged Fatiguing Exercise

Article

Full-text available

Jul 2013
ADV EXP MED BIOL

This study aimed to compare changes in skeletal muscle, prefrontal (PFC), and motor (MC) cortex hemodynamics during prolonged (i.e., 4-h) fatiguing whole-body exercise using multichannel near-infrared spectroscopy (NIRS). Ten subjects completed three successive 80-min cycling bouts at 45 % of their maximal power output. After the 4-h cycling, maximal voluntary contraction force of the leg was decreased by ~25 %. Muscle exhibited reproductive deoxygenation patterns during each of the three bouts, whereas intra-bout cerebral hemodynamics were different throughout the protocol. Results demonstrate that specific responses to fatiguing exercise are found between tissues but also between cortical sites involved in cycling, as shown by concomitant PFC hyperoxygenation and MC deoxygenation in the first 80 min of exercise. Further insights are needed to understand the consequences of these changes regarding the integrative control of motor output while fatigue develops over several hours.

Voluntary exercise can strengthen the circadian system in aged mice

Article

Full-text available

Jan 2013
AGE

Consistent daily rhythms are important to healthy aging according to studies linking disrupted circadian rhythms with negative health impacts. We studied the effects of age and exercise on baseline circadian rhythms and on the circadian system's ability to respond to the perturbation induced by an 8 h advance of the light:dark (LD) cycle as a test of the system's robustness. Mice (male, mPer2luc/C57BL/6) were studied at one of two ages: 3.5 months (n = 39) and >18 months (n = 72). We examined activity records of these mice under entrained and shifted conditions as well as mPER2::LUC measures ex vivo to assess circadian function in the suprachiasmatic nuclei (SCN) and important target organs. Age was associated with reduced running wheel use, fragmentation of activity, and slowed resetting in both behavioral and molecular measures. Furthermore, we observed that for aged mice, the presence of a running wheel altered the amplitude of the spontaneous firing rate rhythm in the SCN in vitro. Following a shift of the LD cycle, both young and aged mice showed a change in rhythmicity properties of the mPER2::LUC oscillation of the SCN in vitro, and aged mice exhibited longer lasting internal desynchrony. Access to a running wheel alleviated some age-related changes in the circadian system. In an additional experiment, we replicated the effect of the running wheel, comparing behavioral and in vitro results from aged mice housed with or without a running wheel (>21 months, n = 8 per group, all examined 4 days after the shift). The impact of voluntary exercise on circadian rhythm properties in an aged animal is a novel finding and has implications for the health of older people living with environmentally induced circadian disruption. Electronic supplementary material The online version of this article (doi:10.1007/s11357-012-9502-y) contains supplementary material, which is available to authorized users.

Time of Day Effects on Repeated Sprint Ability

Article

Full-text available

Jul 2012
INT J SPORTS MED

The present study aimed at investigating the effects of time-of-day on muscle power and associated electromyographic (EMG) activity level of 4 thigh muscles during a repeated pedalling sprint exercise. After a familiarization session, 12 male subjects were asked to perform the repeated sprint ability test during 2 experimental sessions (randomized order), which were set up either at 06:00 or 18:00 h. For each sprint, peak power output, percentage of peak power decrement and total work were calculated. EMG activity of vastus lateralis, rectus femoris, vastus medialis and biceps femoris muscles was recorded throughout the test and analyzed for each sprint. Total work and percentage of peak power decrement were higher in the evening than in the morning (p<0.01 and p<0.05, respectively). Likewise, peak power was significantly higher at 18:00 than 06:00 h during the first 3 sprints (p<0.01 for sprint 1 and p<0.05 for sprint 2 and 3). There was no time-of-day effect for EMG activity level. The neuromuscular efficiency decreased significantly over the repeated sprint ability test at the 2 times of testing (p<0.01). Despite diurnal fluctuation in muscular power and neuromuscular fatigue during the repeated sprint ability test, EMG activity of major thigh muscles was not time-of-day dependent.

Hormonal control of muscle cell growth

Article

Jan 1985

James Ralph Florini

The growth-promoting actions of a number of hormones on muscle have been studied by a number of investigators during the past two decades, and some reasonably solid conclusions can now be reached. The somatomedins and insulin are major stimulators of anabolic processes in skeletal muscle; the last remaining uncertainty (absence of evidence that the somatomedins could replace growth hormone in stimulating weight gain in hypophysectomized animals) has recently been removed. The situation with growth hormone is less clear. Evidence from studies on isolated diaphragm muscles is consistent in indicating responsiveness to growth hormone, but most of it was obtained using supraphysiological levels of the hormone, and (in contrast to somatomedin and insulin) it has not been possible to demonstrate direct effects of this hormone on isolated muscle cells. There are some similar problems in the case of insulin—it is not clear to what extent the anabolic actions of insulin can be attributed to its cross-reaction with the somatomedin receptor and/or its effects on energy metabolism, but there is recent convincing evidence that this hormone has direct anabolic effects on muscle cells in culture. The effects of androgens are much more apparent in the whole animal than in isolated muscles or cell culture systems, and they have been more difficult to characterize. The thyroid hormones are clearly required for normal growth and development in the intact animal, but there is not much information on their actions on isolated muscle or cultured cells. Surprisingly, Cortisol exhibits some growth-promoting effects, but these may be attributable to maintenance of the cells in a “healthy” state rather than to a direct stimulation of anabolic processes. In no case is there any detailed biochemical information on the mechanisms by which any of these growth-promoting actions occur, although it is reasonable to infer that the presence of a cytoplasmic receptor for testosterone in muscle indicates a typical steroid-induced activation of RNA synthesis and a resultant increase in protein synthesis. Thus, although a good deal of progress has been made in cataloging the hormones most likely to have direct effects on the growth of muscle, much remains to be done in determining just how those hormones act.

Improvements in skeletal muscle strength and cardiac function induced by resveratrol during exercise training contribute to enhanced exercise performance in rats

Article

Jan 2012

Cited By (since 1996):11, Export Date: 27 November 2013, Source: Scopus

Respiratory muscle training extends exercise tolerance without concomitant change to peak oxygen uptake: Physiological, performance and perceptual responses derived from the same incremental exercise test

Article

Apr 2013
RESPIROLOGY

Andrew M Edwards

Background and objective: There is conjecture over the efficacy of respiratory muscle training (RMT). The aim of this study was to establish whether or not exercise tolerance, physical performance and effort perceptions are influenced by RMT. Methods: Thirty-six healthy males (age 24 ± 4) agreed to participate (experimental group (EXP) n = 18, control (CON) n = 18). RMT was performed using an inspiratory pressure-threshold training device at either 55% (EXP) or 10% (CON) of maximal inspiratory effort. Measurements of spirometry and maximal static inspiratory mouth pressure were taken before and after 4 weeks of RMT in addition to an incremental test to volitional exhaustion for the determination of: (i) V˙O(2) peak; (ii) maximal velocity at volitional exhaustion (vV˙O(2) peak)); (iii) time to volitional exhaustion; and (iv) effort perceptions. Results: There were no differences in spirometry, but mean maximal static inspiratory mouth pressure increased significantly in EXP (P < 0.01). V˙O(2) peak was unchanged following the 4-week intervention for both EXP and CON, although the proportion of EXP attaining the criteria for a V˙O(2) plateau significantly increased (P < 0.05). Both time to volitional exhaustion (P < 0.05) and vV˙O(2) peak were significantly improved for EXP (P < 0.05), while effort perceptions were reduced (P < 0.05). Conclusions: EXP tolerated higher running velocities during incremental exercise and demonstrated a significant flattening (plateau) of V˙O(2) after training. This suggests that RMT may promote an improved performance outcome vV˙O(2) peak probably as a result of blunted afferent sensations reducing the perceived discomfort of exercise at high ventilatory loads.

Effect of cardiac rehabilitation on muscle mass, muscle strength, and exercise tolerance in diabetic patients after coronary artery bypass grafting

Article

Jan 2013

Background: The effects of cardiac rehabilitation (CR) on muscle mass, muscle strength, and exercise tolerance in patients with diabetes mellitus (DM) who received CR after coronary artery bypass grafting (CABG) have not been fully elucidated. Methods: We enrolled 78 consecutive patients who completed a supervised CR for 6 months after CABG (DM group, n=37; non-DM group, n=41). We measured mid-upper arm muscle area (MAMA), handgrip power (HGP), muscle strength of the knee extensor (Ext) and flexor (Flex), and exercise tolerance at the beginning and end of CR. Results: No significant differences in confounding factors, including age, gender, ejection fraction, or number of CR sessions, were observed between the two groups. At the beginning of CR, the levels of Ext muscle strength and peak VO2 were significantly lower in the DM group than in the non-DM group. At the end of CR, significant improvement in the levels of muscle strength, HGP, and exercise tolerance was observed in both groups. However, the levels of Ext muscle strength, HGP, peak VO2, thigh circumference, and MAMA were significantly lower in the DM group than in the non-DM group. In addition, no significant improvement in thigh circumference and MAMA was observed in the DM group. At the end of CR, the levels of thigh circumference and MAMA correlated with Ext and Flex muscle strength as well as with HGP. Percent changes in the levels of Ext muscle strength were significantly correlated with those of MAMA and hemoglobin A1c. Conclusions: These data suggest that improvement in muscle strength may be influenced by changes in muscle mass and high glucose levels in DM patients undergoing CR after CABG. A CR program, including muscle mass intervention and blood glucose control, may improve deterioration in exercise tolerance in DM patients after CABG.

The diurnal patterns of cortisol and dehydroepiandrosterone in relation to intense aerobic exercise in recreationally trained soccer players

Article

Jun 2012
STRESS

Diurnal patterns of cortisol and dehydroepiandrosterone (DHEA) secretion, the two main peripheral secretory products of the hypothalamic-pituitary-adrenal neuroendocrine stress axis, have been well characterized in rest conditions but not in relation to physical exercise. The purpose of this investigation was therefore to determine the effects of an intense 90-min aerobic exercise on the waking diurnal cortisol and DHEA cycles on three separate days [without exercise, with morning exercise (10:00-11:30 h), and with afternoon exercise (14:00-15:30 h)] in nine recreationally trained soccer players. Saliva samples were collected at awakening, 30 min after awakening, and then every 2 h from 08:00 to 22:00 h. A burst of secretory activity was found for cortisol (p < 0.01) but not for DHEA after awakening. Overall, diurnal decline for both adrenal steroids was observed on resting and exercise days under all conditions. However, there was a significant increase in salivary cortisol concentrations on the morning-exercise and afternoon-exercise days at, respectively, 12:00 h (p < 0.05) and 16:00 h (p < 0.01), versus the other trials. This acute response to exercise was not evident for DHEA. The results of this investigation indicate that 90 min of intense aerobic exercise does not affect the circadian pattern of salivary adrenal steroids in recreationally trained athletes over a 16-h waking period, despite a transitory increase in post-exercise cortisol concentration. Further studies are necessary to determine whether these results are applicable to elite athletes or patients with cortisol or DHEA deficiency.

Morning and evening exercise

Abstract

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