Morning Exercise Research Articles

The effects of sex, metabolic syndrome and exercise on postprandial lipemia

ObjectiveExercise has been suggested to have cardioprotective benefits due to a lowering of postprandial triglycerides (PPTG). We hypothesized that a morning exercise bout would significantly lower PPTG measured over a full day, in response to moderate fat meals (35% energy) in men more so than women, and in metabolic syndrome (MetS) relative to normal weight (NW) individuals. Materials/MethodsParticipants completed two randomized study days; one control and one exercise day (60min of morning exercise, 60% VO2peak). Meals were consumed at breakfast, lunch and dinner with the energy expended during exercise replaced on the active day. The areas (AUC) and incremental areas (IAUC) under the curve were calculated for total triglycerides, total cholesterol and other metabolites. ResultsExercise did not significantly change the PPTG AUC & IAUC overall, or within, or between, each sex or group (NW and MetS). Exercise induced a 30% decrease in total cholesterol IAUC (p=0.003) in NW subjects. Overall, women had a lower IAUC for PPTG compared to men (p=0.037), with the greatest difference between MetS women and MetS men, due to a sustained drop in TG after lunch in the women. This suggests that PP, rather than fasting, lipid analyses may be particularly important when evaluating sex differences in metabolic risk. ConclusionsWith energy replacement, moderate morning exercise did not result in a significant decrease in PPTG excursions. Exercise did elicit a significant decrease in PP cholesterol levels in NW subjects, suggesting a potential mechanism for the cardioprotective effects of exercise.

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

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.

Fast eating and the risk of type 2 diabetes mellitus: A case-control study

The aim of the study was to assess the relationship between eating speed and the risk of type 2 diabetes mellitus. A case-control study included 234 cases with newly diagnosed type 2 diabetes and 468 non diabetic controls. A specifically designed questionnaire was used to collect information on possible risk factors of type 2 diabetes. The speed of eating was self-reported by study subjects compared to other subjects, with whom they were eating at the same table. The odds ratios (OR), and 95% confidence intervals (95% CI) for type 2 diabetes were calculated by a conditional logistic regression. Variables such as a family history on diabetes, body mass index, waist circumference, educational level, morning exercise, smoking and plasma triglycerides level were retained in multivariate logistic regression models as confounders because their inclusion changed the value of the OR by more than 5% in any exposure category. After adjustment for possible confounders more than two-fold increased risk of type 2 diabetes was determined for subjects eating faster (OR=2.52; 95% CI 1.56-4.06) vs. subjects eating slower. Our data support a possible relationship between faster eating speed and the increased risk of type 2 diabetes mellitus.

The Early Bird Gets the Worm: How Early Morning Exercise Creates Inspired Learners and Educators

As the nation grapples with how to shrink the achievement gap and raise the level of achievement for all students, educators need to rethink how they deliver instruction and how students learn. Sitting in chairs all day long is not the most conducive way to learn. It is critical that schools look towards morning movement and exercise programs to stimulate increased brain activity and energize children to be ready and able to focus on their academics throughout the day.

Exercise facilitates memory: Implications for helping youngsters learn in school☆

Up to this day I still can vividly remember a routine in my elementary school: the daily school-wide morning calisthenics. It started at about 7:45 am in the school courtyard. Our physical education teacher stood on the concrete stage where our principal would give her talk at school assemblies. All children and teachers would follow the teacher's lead to do the eight-segment national calisthenics in unison with loud music from loudspeakers affixed on trees around the courtyard. When I visited the school last May, I saw that students still performed the routine faithfully but with a different set of calisthenics program. The principal said, exactly like what my principal would, that the morning exercise could help students learn in classroom by following the “Three-Excellence” doctrine: excellent health, excellent learner, and excellent citizen.

Egg consumption and the risk of type 2 diabetes mellitus: a case–control study

Type 2 diabetes mellitus appears to involve an interaction between susceptible genetic backgrounds and environmental factors including highly calorific diets. As it is important to identify modifiable risk factors that may help reduce the risk of type 2 diabetes mellitus, the aim of the present study was to determine the association between egg consumption and the risk of type 2 diabetes mellitus. A specifically designed questionnaire was used to collect information on possible risk factors of type 2 diabetes mellitus. The odds ratios and 95 % confidence intervals for type 2 diabetes mellitus were calculated by conditional logistic regression. A case-control study in a Lithuanian out-patient clinic was performed in 2001. A total of 234 cases with a newly confirmed diagnosis of type 2 diabetes mellitus and 468 controls free of the disease. Variables such as BMI, family history of diabetes, cigarette smoking, education, morning exercise and plasma TAG level were retained in multivariate logistic regression models as confounders because their inclusion changed the value of the odds ratio by more than 10 % in any exposure category. After adjustment for possible confounders more than twofold increased risk of type 2 diabetes mellitus was determined for individuals consuming 3-4·9 eggs/week (OR = 2·60; 95 % CI 1·34, 5·08) and threefold increased risk of the disease was determined for individuals consuming ≥5 eggs/week (OR = 3·02; 95 % CI 1·14, 7·98) compared with those eating <1 egg/week. Our data support a possible relationship of egg consumption and increased risk of type 2 diabetes mellitus.

Core temperature response to cycling exercise: Effect of time of day and measurement site

This study evaluated the effect of time of day and temperature measurement site on core temperature response to exercise. Six trained cyclists performed a 1h cycling exercise at a fixed power-output of 160W in a controlled environment (ambient temperature of 21.5±1.6°C and relative humidity of 31±6%) at batyphase +2h (08:00h) and acrophase +2h (20:00h) of their estimated circadian temperature rhythm; corresponding respectively to the heat gain and heat loss mode phases. Throughout the exercise, rectal and gastro-intestinal temperature data were collected. A two-way ANOVA was applied and a common nonlinear logistic-type function dependant on three parameters (asymptote, xmid and scale) was used to fit collected data. ANOVA only indicated a time of day effect without interaction with exercise duration. A nonlinear mixed-effect model allowed further analysis of temperature kinetics. The model indicated a higher theoretical increase in temperature at the end of morning exercise compared to the evening session. However, the circadian difference observed at rest persists throughout the exercise. Theoretical asymptotic temperature values at the end of the exercise and scale values (inversely proportional to the slope) are higher for the rectal measurement site than for the gastro-intestinal measurement. The model proposed offers a solution for refining the study of individual core temperature response to prolonged exercise. The main advantage is that it takes into consideration intra- and inter-individual variability in temperature kinetics.

The Influence of Acute Morning and Evening Exercise on Homocysteine, Fibrinogen and Platelet

The Influence of Acute Morning and Evening Exercise on Homocysteine, Fibrinogen and Platelet cardiac disease ,there are discrepancies regarding the safety or priority of morning or evening exercise in this regard. Some studies indicate that acute ischemic events show a circadian rhythm which correlate with increased activity of the sympathetic nervous system and increased platelet aggregation during early morning

Impacts of pedometer determined physical activity on biochemical risk factors of the cardiovascular system

Physical activity (PA) volume is an important element in maintaining health and functional ability in the population and has a useful effect on lipid profile. Walking is a preferred choice and as a current movement pattern in PA and several social jobs. The aim of this present study was to evaluate the effects of daily number of steps on the blood lipid profile in middle age men. Daily steps volumes were measured in the healthy men (n = 108) by the pedometer. Subjects voluntarily selected as an active group (AG) and sedentary group (SG). In addition, total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) were measured. The averages of daily steps in the AG (12632±3957 steps/day) were significantly higher than SG (5347±1631step/day) (P 0.05). It seems that the middle aged sedentary populations were at least 12,500 steps/day accordant with PA, and morning exercise programs as a threshold of anti–risk factor can improve the cardiovascular system efficiency. Key words: physical activity, biochemical risk factor, steps per day, pedometer.

Effects of moderate aerobic exercise training on chronic primary insomnia

To evaluate the effect of long-term moderate aerobic exercise on sleep, quality of life, and mood of individuals with chronic primary insomnia, and to examine whether these effects differed between exercise in the morning and exercise in the late afternoon. Nineteen sedentary individuals with chronic primary insomnia, mean age 45.0 (standard error [SE] 1.9) years, completed a 6-month exercise training protocol, randomized to morning and late-afternoon exercise groups. Combining polysomnographic data across both time points, this study found a significant decrease in sleep onset latency (from 17.1 [SE 2.6] min to 8.7 [SE 1.4] min; P<0.01) and wake time after sleep onset (from 63.2 [SE 12.8] min to 40.1 [SE 6.0] min), and a significant increase in sleep efficiency (from 79.8 [SE 3.0]% to 87.2 [SE 1.6]%) following exercise. Data from sleep diaries revealed significant improvement in sleep onset latency (from 76.2 [SE 21.5] min to 80.3 [SE 7.4] min) sleep quality (from 41.5 [SE 5.2]% to 59.4 [SE 6.6]%) and feeling rested in the morning (from 50.8 [SE 5.3] to 65.1 [SE 5.0]). There were generally no significant differences in response between morning and late-afternoon exercise. Following exercise, some quality-of-life measures improved significantly, and a significant decrease was seen in the following Profile of Mood State measures: tension-anxiety (from 7.2 [SE 1.0] to 3.5 [SE 1.0]), depression (from 5.9 [SE 1.2] to 3.3 [SE 1.1]) and total mood disturbance (from 9.2 [SE 4.8] to -1.7 [SE 4.8]). These effects did not vary between morning and late-afternoon exercise. Long-term moderate aerobic exercise elicited significant improvements in sleep, quality of life and mood in individuals with chronic primary insomnia.

Effect of morning exercise in sunlight on the sleep-wake cycle in adolescents.

A delay in bedtime occurs in adolescence compared with childhood. However, the early waking that morning school hours impose leads to partial sleep deprivation. Although exposure to light is the most important regulator of circadian rhythm in mammals, physical exercise influences circadian synchronization. To assess the effect of morning physical exercise in sunlight on the sleep-wake cycle (SWC) in adolescents, 160 first- and second-year high-school students were exposed to classes in their usual classroom (Group C) or in a swimming pool exposed to sunlight (Group E) while physically exercising (EE; i.e., swimming) or resting (EL). At baseline, we applied Health and Sleep and Horne & Ostberg chronotype assessment questionnaires. One week later and during the intervention, we applied the Sleep Diary and Karolinska Sleepiness Scale. During the intervention we observed no changes in bedtime, time in bed and in indices of irregularity of bedtime and wake-up time. The changes observed in wake-up time (i.e., a delay in the EE group on Saturday), sleep quality (i.e., an improvement), and sleepiness (i.e., an increase) were also observed in the control group, discarding an intervention effect. We suggest that morning physical exercise in sunlight had no effect on SWC parameters, sleep quality, or daytime sleepiness, possibly because of the large irregularity in the SWC between weekdays and weekends in adolescent students as well as the low frequency and duration of exercise during the intervention. Therefore, studies that evaluate a higher frequency or duration of exercise are needed to assess its effect on the SWC in adolescents.

Diurnal variation in the salivary melatonin responses to exercise: relation to exercise-mediated tachycardia

Salivary melatonin concentration is an established marker of human circadian rhythmicity. It is thought that melatonin is relatively robust to the masking effects of exercise. Nevertheless, the extent and even the direction of exercise-related change is unclear, possibly due to between-study differences in the time of day exercise is completed. Therefore, we aimed to compare melatonin responses between morning and afternoon exercise, and explore the relationships between exercise-related changes in melatonin and heart rate. At 08:00 and 17:00hours, seven male subjects (mean±SD age, 27±5years) completed 30min of cycling at 70% peak oxygen uptake followed by 30min of rest. Light intensity was maintained at ~150lx. Salivary melatonin (ELISA) and heart rate were measured at baseline, 15min during exercise, immediately post-exercise and following 30min recovery. Melatonin was ≈15pgml(-1) higher in the morning trials compared with the afternoon (P=0.030). The exercise-related increase in melatonin was more pronounced (P=0.024) in the morning (11.1±8.7pgml(-1)) than in the afternoon (5.1±5.7pgml(-1)). The slope of the heart rate-melatonin relationship was significantly (P=0.020) steeper in the morning (0.12pgml(-1)beats(-1)min(-1)) than in the afternoon (0.03pgml(-1)beats(-1)min(-1)). In conclusion, we report for the first time that the masking effect of moderate-intensity exercise on melatonin is approximately twice as high in the morning than the afternoon. The much steeper relationship between heart rate and melatonin changes in the morning raises the possibility that time of day alters the relationships between exercise-mediated sympathetic nervous activity and melatonin secretion.

Lack of Effect of Exercise Time of Day on Acute Energy Intake in Healthy Men

Although the manipulation of exercise and dietary intake to achieve successful weight loss has been extensively studied, it is unclear how the time of day that exercise is performed may affect subsequent energy intake. The purpose of the current study was to investigate the effect of an acute bout of exercise performed in the morning compared with an equivalent bout of exercise performed in the afternoon on short-term energy intake. Nine healthy male participants completed 3 trials: morning exercise (AM), afternoon exercise (PM), or control (no exercise; CON) in a randomized counterbalanced design. Exercise consisted of 45 min of treadmill running at 75% VO(2peak). Energy intake was assessed over a 26-hr period with the participants eating ad libitum from a standard assortment of food items of known quantity and composition. There was no significant difference in overall energy intake (M ± SD; CON 23,505 ± 6,938 kJ, AM 24,957 ± 5,607 kJ, PM 24,560 ± 5,988 kJ; p = .590) or macronutrient preferences during the 26-hr period examined between trials. Likewise, no differences in energy intake or macronutrient preferences were observed at any of the specific individual meal periods examined (i.e., breakfast, lunch, dinner) between trials. These results suggest that the time of day that exercise is performed does not significantly affect short-term energy intake in healthy men.

Morning or evening exercise: effects on the heart rate circadian rhythm above the Arctic Circle

The potency of exercise as a nonphotic time cue compared to the solar cycle in influencing entrainment (organism synchronization within the 24-h period) has yet to be defined. Above the Arctic Circle during winter the sun remains below the horizon for several weeks and during summer remains above the horizon for several weeks. The goal of the present study was to investigate the effects related to exercising time on the circadian structure under conditions of lack of daylight and continuous daylight. The experiments were carried out at 70° North, above the Arctic Circle. Ten healthy females (age 24±5 years) were divided into two groups: an exercise and a control group. The subjects in the exercise group performed the same exercise routine at two different times of day (0900 and 1800 hours) both in January (twilight period) and in May (continuous daylight period). Continuous heart rate data were collected and analysed by the cosinor method. The acrophase values were significantly modified in the exercise group during evening exercise in January showing a delay compared with morning exercise and compared with the control group (3 h and 1.5 h, respectively), while in May this effect was not seen. The results indicate that in continuous daylight, the potency of exercise in modulating the circadian phase seems to be suppressed. However, these findings need to be verified in a larger poulation.

Using Squat Repetition Maximum Testing to Determine Hamstring Resistance Training Exercise Loads

The purpose of this study was to determine whether there is a linear relationship between the squat and a variety of hamstring resistance training exercises, and whether this relationship differs on the basis of sex. This study also sought to create prediction equations for the determination of hamstring exercise load based on the squat load. Repetition maximums of the squat, as well as 4 common hamstring resistance training exercises including the seated leg curl, stiff leg dead lift, single leg dead lift, and good morning exercise, were determined for each subject. Subjects included 21 men and 13 women collegiate athletes. Data were evaluated using linear regression analysis to predict hamstring exercise loads from 6 repetition maximum squat data. Results of the analysis of all subjects indicated that squat load was a significant predictor of loads for each of the hamstring exercises. However, separate analysis of women revealed that squat load was not a significant predictor of loads for any of the hamstring exercises. Analysis of the men revealed that squat was a significant predictor of load for the seated leg curl (R = 0.58, p < 0.001), stiff leg dead lift (R = 0.82, p < 0.001), single leg stiff leg dead lift (R = 0.80, p < 0.001), and good morning (R = 0.79, p < 0.001) exercises. On the basis of the analysis of the men, the following prediction equations were devised for each exercise: (1) seated leg curl load = squat load (0.186) + 10.935 kg, (2) stiff leg deadlift load = squat load (1.133) - 86.331 kg, (3) single leg stiff leg deadlift load = squat load (0.443) - 3.425 kg, and (4) good morning load = squat load (0.961) - 105.505 kg. Thus, results from testing core exercises such as the squat can provide useful data for the assignment of loads for assistance exercises.

Isokinetic Leg Strength Profile of Elite Male Basketball Players

The purpose of this study was to document the muscle activity, spine motion, spine load, and stiffness during several movement-based or "functional" exercises and to assess the effect of technique change. Eight subjects, all healthy men from a university population, were instrumented to obtain surface electromyography of selected trunk and hip muscles, together with video analysis and electromagnetic lumbar spine position sensor to track spine posture. Exercises included a walkout in the sagittal plane that compared an upright form against a wall with those performed on the floor, overhead cable pushes, lateral cable walkouts, the good morning exercise, and the bowler's squat. Generally, muscle activation levels were quite modest even though the tasks were quite strenuous in many cases. Even though similar joint moments were required in different exercises, the pattern of activity between muscles was different. Abdominal bracing increased spine stiffness at the expense of more spine load. Thus, muscle activity seems to be constrained in "functional" exercises. There are several possible reasons for this. Single muscles cannot be activated to 100% of the maximum voluntary contraction in functional exercises because this would upset the balance of moments about the 3 orthopedic axes of the spine, or it would upset the balance of stiffening muscles around the spine required to ensure stability of the spinal column. The one exception was the floor walkout, which resulted in full activation of the rectus abdominis; however, this was a sagittal plane task without the joint moment constraints of multiplanar exercise. Therefore, maximal muscle activity is observed during single-plane tasks, but muscle activation levels were constrained during functional tasks. Thus, strength training muscles may not help in "functional multiplanar" tasks. These data can be used to assist decisions regarding the selection of exercises, specifically choices regarding the starting challenge, progression, exercise form, and possibly corrective technique for those who have spine concerns, or those simply looking for performance enhancement.

Evidence for a Greater Elevation in Vascular Shear Stress after Morning Exercise

The vascular endothelium plays an important role in the maintenance of vascular health and the modulation of vascular tone and blood pressure. Recently, it has been demonstrated that blood pressure reactivity to physical activity is greater in the morning, and possibly, diurnal variation in vascular function may also be evident. The aim of this study was to assess vascular responses after exercise at different times of day. After 45 min of supine rest, 12 male normotensives completed a 30-min bout of cycling at 70% peak oxygen uptake beginning on separate days at 0800 and 1600 h. Edge detection and wall tracking of high-resolution arterial B-mode ultrasound images combined with synchronized Doppler waveform analysis were used to measure brachial and femoral conduit artery diameter and to calculate blood flow and shear rate. Measurements were recorded before and 20 min after exercise. At 5 min after exercise, the mean +/- SE brachial shear rate was 72 +/- 21 arbitrary unit (AU) higher in the morning compared with the afternoon (P = 0.05), but this was not compensated for by enlargement of arterial diameter (P = 0.59). No diurnal variation was observed in the femoral artery measurements. Diurnal difference in conduit artery regulatory control manifests as an elevated intravascular shear stress after morning exercise. Potentially, higher postexercise shear rate in the morning in at-risk individuals could contribute to the elevated cardiovascular risk evident in the postwaking hours.

Actigraphy Assessment Of The Effects Of Circuit Training Exercise On Sleep In Healthy, Morning-type Women

PURPOSE: The purpose of this study was (1) to compare wrist actigraphy-derived nocturnal sleep characteristics of healthy, morning-type women between non-exercise days and structured exercise program (circuit training class) days, and (2) to examine whether a change in the regular time-of-day of their established exercise routine from the morning hours to the early evening hours affects sleep. METHODS: Fifteen healthy, morning-type women (age: 47.4±5.5 yrs) were recruited for this study. All subjects were following an established (6 weeks or longer) morning (between 7am-9am) exercise training routine that consisted of a 60 min, personal trainer supervised, moderate-intensity, circuit-training program at a commercial fitness facility. For purpose of this study, sleep/wake patterns were determined from 24-hour wrist actigraphy (AW 64 Actiwatch) recordings over five successive weekdays. During three of these five weekdays, subjects did not participate in any formal exercise training sessions. On the remaining two (always non-consecutive) days, subjects completed their regular circuit training classes on one day during their normal morning hours and on the other day it was changed to the evening hours (between 5pm-7pm). Actigraphy data were scored using the Actiware (version: 5.0) sleep analysis software (Mini Mitter, Bend, OR) for the assessment of total sleep time (TST), sleep onset latency (SOL), wake after sleep onset (WASO), and sleep efficiency (SE). RESULTS: Descriptive means (±SD) for the global score on the Pittsburgh Sleep Quality Index and the Beck Depression Inventory for the study cohort was 4.33 (±2.94) and 3.64 (±3.65), respectively. Repeated measures ANOVA revealed no significant differences between actigraphy-derived nocturnal sleep characteristics for TST, SOL, WASO, and SE between non-exercise and normal morning exercise days (>0.05). Moreover, changing the habitual exercise training routine from the morning hours to the early evening hours failed to have a significant effect on these sleep measures (p>0.05). CONCLUSIONS: Moderately intense circuit training exercise, either performed during a regular accustomed morning training time period or when changed to an unaccustomed early evening time period, does not seem to influence the normal sleep of healthy, morning-type women.

Coffee consumption and type 2 diabetes mellitus

The aim of the study was to determine the association between coffee consumption and the risk of type 2 diabetes mellitus. A case-control study included 234 cases with newly confirmed diagnosis of type 2 diabetes mellitus and 468 controls who were free of the disease in 2001. Cases and controls were matched by gender and age (+/-5 years). Data on age, education level, occupation status, marital status, family history of diabetes, lifestyle (dietary habits, smoking habits, coffee consumption, alcohol consumption, physical activity), and stress were collected via a questionnaire. Variables were retained in models as confounders when their inclusion changed the value of the OR by more than 10% in any exposure category. Conditional logistic regression to compute the odds ratio (OR), 95% confidence interval (CI), and P for trend was used. After adjustment for possible confounders (family history of diabetes, body mass index, eating speed, morning exercise, cigarette smoking, years of education, and stress), a statistically significant relationship was observed between type 2 diabetes mellitus and coffee consumption. Individuals consuming four or more cups of coffee per day were at lower risk of 2 diabetes mellitus (OR=0.51; 95% CI, 0.27-0.97) compared to those who consumed one or less than one cup of coffee per day. Habitual coffee consumption of four or more cups per day might be related to the lower risk of type 2 diabetes mellitus.

Effect of exercise time of day on energy intake in normal weight males

Introduction: Although the manipulation of exercise and dietary intake to achieve successful weight loss has been extensively studied, the effect of exercise itself on energy intake is not well understood. The purpose of this study was to investigate the effect of the time of day that exercise is performed (morning compared to afternoon) on short-term energy intake. Methodology: Nine healthy male participants completed three trials; morning exercise, afternoon exercise and control (no exercise) in a random crossover design.