Thursday, December 11, 2014

Running performance is impaired by mental fatigue

Posted on December 11, 2014 by Stone Hearth News


Med Sci Sports Exerc. 2014 Dec 9. [Epub ahead of print]

Mental Fatigue Impairs Intermittent Running Performance.

Smith MR1, Marcora SM, Coutts AJ. Author information 11Sport and Exercise Discipline Group, Faculty of Health, University of Technology Sydney, Australia.

2Endurance Research Group, School of Sport and Exercise Sciences, University of Kent at Medway, United Kingdom.

Abstract

PURPOSE:

To investigate the effects of mental fatigue on intermittent running performance.

METHODS:

Ten male intermittent team sports players performed two identical self-paced intermittent running protocols. The two trials were separated by seven days and preceded, in a randomised-counterbalanced order, by 90 min of either emotionally-neutral documentaries (control) or the AX-continuous performance test (AX-CPT; mental fatigue). Subjective ratings of fatigue and vigor were measured before and after these treatments, and motivation was recorded prior to the intermittent running protocol. Velocity, heart rate, oxygen consumption, blood glucose and lactate concentrations, and ratings of perceived exertion (RPE) were measured throughout the 45-min intermittent running protocol. Session-RPE was recorded 30 min after the intermittent running protocol.

RESULTS:

Subjective ratings of fatigue were higher following the AX-CPT (P = 0.005). This mental fatigue significantly reduced velocity at low intensities (1.28 ± 0.18 m⋅s vs. 1.31 ± 0.17 m⋅s; P = 0.037), while high-intensity running and peak velocities were not significantly affected. Running velocity at all intensities significantly declined over time in both conditions (P < 0.001). Oxygen consumption was significantly lower in the mental fatigue condition (P = 0.007). Other physiological variables, vigor and motivation were not significantly affected. RPE during the intermittent running protocol was not significantly different between conditions despite lower overall velocity in the mental fatigue condition. Session-RPE was significantly higher in the mental fatigue condition

CONCLUSION:

Mental fatigue impairs intermittent running performance. This negative effect of mental fatigue appears to be mediated by higher perception of effort.

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Wednesday, December 10, 2014

Vitamin C may help people who suffer from respiratory symptoms after exercise

Posted on December 8, 2014 by Stone Hearth News

Physical activity increases oxidative stress, and therefore, as an antioxidant vitamin C might have particularly evident effects on people who are participating in vigorous exercise. In several studies, vitamin C administration attenuated the increases in oxidative stress markers caused by exercise. Furthermore, vitamin C is involved in the metabolism of histamine, prostaglandins, and cysteinyl leukotrienes, all of which appear to be mediators in the pathogenesis of exercise-induced bronchoconstriction.

A meta-analysis of three studies found that vitamin C halved post-exercise FEV1 decline in participants who suffered from exercise-induced bronchoconstriction. Five other studies examined subjects who were under short-term, heavy physical stress and a meta-analysis revealed that vitamin C halved the incidence of respiratory symptoms. Another trial reported that vitamin C halved the duration of the respiratory symptoms in male adolescent competitive swimmers.

FEV1 is the standard pulmonary function outcome for assessing whether a person suffers from exercise-induced bronchoconstriction. However, exercise-induced decline in FEF25-75 is twice as great as the decline in FEV1. FEV1 measures the large-airway obstruction, whereas FEF25-75 measures small-airway obstruction. Therefore, FEF25-75 or the closely related FEF50 might provide relevant additional information about the possible effects of vitamin C.

Harri Hemila, MD, PhD, of the University of Helsinki, Finland, carried out a secondary analysis of a study which had 12 participants. The participants had asthma, were on average 26 years, and suffered from exercise-induced bronchoconstriction. The FEV1 and FEF60 levels before and after exercise were reported on vitamin C and placebo days, but the data was not thoroughly analyzed originally.

In five out of the 12 participants, exercise caused a decline greater than 60% in FEF60. Such a dramatic FEF60 decline indicates that the absolute post-exercise level of FEF60 becomes an important outcome in its own right, in addition to its change from the pre-exercise level. Vitamin C administration increased the post-exercise FEF60 level in these 5 participants by between 50% and 150%. In contrast, no mean difference between the vitamin C and placebo days was detected in the other 7 participants.

– The increase in post-exercise FEF60 level by vitamin C is a novel finding, which indicates that vitamin C may have substantial effects on the small airways, Dr. Hemilä states.

Dr. Hemila concludes that “given the safety and low cost of vitamin C, and the consistency of positive findings in the nine randomized trials on vitamin C against exercise-induced bronchoconstriction and respiratory symptoms, it seems reasonable for physically active people to test whether vitamin C is beneficial on an individual basis, if they have documented exercise-induced bronchoconstriction or suffer from respiratory symptoms such as cough or sore throat after taking vigorous exercise.” Source Real Cause, Real Cure: The 9 root causes of the most common health problems and how to solve them

Follow these topics: Exercise: Benefits, Nutrition: Vitamin C, Respiratory - See more at: http://www.stonehearthnewsletters.com/vitamin-c-may-help-people-who-suffer-from-respiratory-symptoms-after-exercise/benefits-exercise/#sthash.7BJwn3hJ.dpuf

The effect of abdominal strength or endurance exercises on abdominal peak torque and endurance field tests of healthy participants: A randomized controlled trial

Posted on December 8, 2014 by Stone Hearth News

Phys Ther Sport. 2014 Sep 9. pii: S1466-853X(14)00073-X. doi: 10.1016/j.ptsp.2014.08.009. [Epub ahead of print]

The effect of abdominal strength or endurance exercises on abdominal peak torque and endurance field tests of healthy participants: A randomized controlled trial.

Learman K1, Pintar J2, Ellis A3. Author information 1Department of Physical Therapy, Youngstown State University, One University Plaza, Youngstown, OH 44555, USA.

Electronic address: klearman@ysu.edu. 2Department of Human Performance and Exercise Science, Youngstown State University, One University Plaza, Youngstown, OH 44555, USA. 3Department of Physical Therapy, Youngstown State University, One University Plaza, Youngstown, OH 44555, USA.

 Abstract

OBJECTIVE:

To compare the effects of muscular endurance and resisted strengthening protocols on abdominal strength and endurance in a sample of young subjects.

DESIGN:

Randomized Clinical Trial. SETTING: University fitness laboratory.

PARTICIPANTS:

79 healthy subjects, (45 males and 34 females) aged 23.5 ± 5.8 years.

MAIN OUTCOME MEASURES:

Measurements were taken at baseline and 12 weeks. Abdominal strength and endurance were evaluated using an isokinetic dynamometer (IKD) and four floor tests including the timed front plank (FP), angle sit (AS), sit-up (SU), and handheld dynamometer (HD).

RESULTS:

Multivariate analysis revealed no between group differences for the outcomes or group × time interaction (P = 0.52 and P = 0.31 respectively). The univariate within group analysis was significant for SU P = .001, HD rectus P = .007, HD oblique P = .005, and for the IKD peak eccentric torque P = .025.

A 12-week intervention program addressing endurance or strength did not produce between-group differences over a control group of routine activity maintenance.

Source #1 Strength Training Abdominal Belt: BEST Core Strength Workout for Core Training & Core Fitness Follow these topics: Fitness: Endurance Training

Monday, December 8, 2014

The effects of horse riding simulation exercise on muscle activation and limits of stability in the elderly

Posted on December 6, 2014 by Stone Hearth News

Arch Gerontol Geriatr. 2014 Nov 7. pii: S0167-4943(14)00197-6. doi: 10.1016/j.archger.2014.10.018. [Epub ahead of print]

The effects of horse riding simulation exercise on muscle activation and limits of stability in the elderly.

Kim SG1, Lee JH2.

Author information 1Department of Physical Therapy, Rehabilitation Science College, Daegu University, 15,

Jilyang, Gyeongsan-si, Gyeongbuk 712-714, Republic of Korea(1).

2Department of Physical Therapy, Kyungdong University, 5, Doriwon-gil, Sokcho,Gangwon-do 217-711, Republic of Korea. Electronic address: ljhcivapt@naver.com.

Abstract

This study aimed to investigate the effect of horse riding simulation (HRS) on balance and trunk muscle activation as well as to provide evidence of the therapeutic benefits of the exercise. Thirty elderly subjects were recruited from a medical care hospital and randomly divided into an experimental and a control group. The experimental group performed the HRS exercise for 20min, 5 times a week, for 8 weeks, and conventional therapy was also provided as usual. The muscle activation and limits of stability (LOS) were measured. The LOS significantly increased in the HRS group (p<0.05) but not in the control group (p>0.05). The activation of all muscles significantly increased in the HRS group. However, in the control group, the muscle activations of the lateral low-back (external oblique and quadratus lumborum) and gluteus medius (GM) significantly decreased, and there was no significant difference in other muscles. After the intervention, the LOS and all muscle activations significantly increased in the HRS group compared with the control group. The results suggest that the HRS exercise is effective for reducing the overall risk of falling in the elderly. Thus, it is believed that horse riding exercise would help to increase dynamic stability and to prevent elderly people from falling.

Source

Why does physical activity during childhood matter?

Posted on December 7, 2014 by Stone Hearth News


Over the past thirty years, physical activity among children has declined markedly. The public health implications of this decline include a growing prevalence of obesity and chronic diseases such as diabetes and hypertension. A new issue of Monographs of the Society for Research in Child Development expands the focus to ask whether physical activity is also related to children’s brain and cognitive development and achievement in school.

Scholarly articles published by over 20 researchers in Monographs, titled “The Relation of Childhood Physical Activity to Brain Health, Cognition and Scholastic Achievement” indicate that while physical activity in schools has diminished in part because of a growing emphasis on student performance and academic testing, decreased physical activity is actually related to decreased academic performance. Approximately 55.5 million children are enrolled in pre-kindergarten – 12th grade in the United States in a given academic year. According to research presented in Monographs, while there is variation across states and schools, overall, opportunities to engage in physical activity have diminished. Current U.S. Department of Health and Human Services guidelines call for children to have a minimum of 60 minutes of intermittent physical activity per day. However, in 2012, according to the Centers for Disease Control and Prevention, only 30 percent of children attended a school in which they were offered physical education daily.

 The majority of students do not engage in any form of planned physical activity during the school week. Yet physically active children tend to outperform their inactive peers in the classroom and on tests of achievement. The research presented in the monograph helps to make clear why. When compared to their less fit peers, those who engage in more physical activity have larger brain volumes in the basal ganglia and hippocampus, areas associated with cognitive control and memory. Cognitive control refers to the control of thought, action, behavior, and decision-making.

Physically active children also have increased concentration and enhanced attention spans when compared to their less active peers. The authors find that fitness is related to the ability to inhibit attention to competing stimuli during a task, an ability that can help children stay focused and persevere to complete an assignment.

The findings on attention encompass children with special needs as well as typically developing children. The authors also report on physical activity as a non-pharmaceutical intervention for children with attention-deficit/hyperactivity disorder and children with autism spectrum disorders, with positive results. According to Dr. Charles Hillman, professor of kinesiology and community health at the University of Illinois at Urbana-Champaign and lead author on this issue of Monographs, “these results point to the important potential of approaches focusing on physical activity for strengthening children’s brain health and educational attainment.

It is important for state governments and school administrators to consider this evidence and promote physical activity in the school setting, which is where children spend much of their time.” Hillman also notes that the findings in the monograph come not only from studies looking at variation in physical activity and fitness level as they occur spontaneously among children, but also from studies in which children are randomly assigned to physical activity interventions or to continue their ongoing activity levels. This helps to assure that the links between physical activity, brain development and achievement are actually caused by the differences in activity rather than reflecting the characteristics of the children who choose to be more or less physically active.

Source - See more at: http://www.stonehearthnewsletters.com/why-does-physical-activity-during-childhood-matter/benefits-exercise/#sthash.0RRKvaQ8.dpuf

Tuesday, November 4, 2014

The mind-body connection: Clear new evidence

Posted on November 3, 2014 by Stone Hearth News


For the first time, researchers have shown that practising mindfulness meditation or being involved in a support group has a positive physical impact at the cellular level in breast cancer survivors.

A group working out of Alberta Health Services’ Tom Baker Cancer Centre and the University of Calgary Department of Oncology has demonstrated that telomeres – protein complexes at the end of chromosomes – maintain their length in breast cancer survivors who practise meditation or are involved in support groups, while they shorten in a comparison group without any intervention.

Although the disease-regulating properties of telomeres aren’t fully understood, shortened telomeres are associated with several disease states, as well as cell aging, while longer telomeres are thought to be protective against disease.

“We already know that psychosocial interventions like mindfulness meditation will help you feel better mentally, but now for the first time we have evidence that they can also influence key aspects of your biology,” says Dr. Linda E. Carlson, PhD, principal investigator and director of research in the Psychosocial Resources Department at the Tom Baker Cancer Centre.

“It was surprising that we could see any difference in telomere length at all over the three-month period studied,” says Dr. Carlson, who is also a U of C professor in the Faculty of Arts and the Cumming School of Medicine, and a member of the Southern Alberta Cancer Institute. “Further research is needed to better quantify these potential health benefits, but this is an exciting discovery that provides encouraging news.”

 The study was published online today in the journal Cancer. It can be found at: http://onlinelibrary.wiley.com/doi/10.1002/cncr.29063/full

A total of 88 breast cancer survivors who had completed their treatments for at least three months were involved for the duration of the study. The average age was 55 and most participants had ended treatment two years prior. To be eligible, they also had to be experiencing significant levels of emotional distress.

In the Mindfulness-Based Cancer Recovery group, participants attended eight weekly, 90-minute group sessions that provided instruction on mindfulness meditation and gentle Hatha yoga, with the goal of cultivating non-judgmental awareness of the present moment. Participants were also asked to practise meditation and yoga at home for 45 minutes daily.

In the Supportive Expressive Therapy group, participants met for 90 minutes weekly for 12 weeks and were encouraged to talk openly about their concerns and their feelings. The objectives were to build mutual support and to guide women in expressing a wide range of both difficult and positive emotions, rather than suppressing or repressing them.

The participants randomly placed in the control group attended one, six-hour stress management seminar.

All study participants had their blood analysed and telomere length measured before and after the interventions.

Scientists have shown a short-term effect of these interventions on telomere length compared to a control group, but it’s not known if the effects are lasting. Dr. Carlson says another avenue for further research is to see if the psychosocial interventions have a positive impact beyond the three months of the study period.

Allison McPherson was first diagnosed with breast cancer in 2008. When she joined the study, she was placed in the mindfulness-based cancer recovery group. Today, she says that experience has been life-changing.

“I was skeptical at first and thought it was a bunch of hocus-pocus,” says McPherson, who underwent a full year of chemotherapy and numerous surgeries. “But I now practise mindfulness throughout the day and it’s reminded me to become less reactive and kinder toward myself and others.”

Study participant Deanne David was also placed in the mindfulness group. “Being part of this made a huge difference to me,” she says. “I think people involved in their own cancer journey would benefit from learning more about mindfulness and connecting with others who are going through the same things.”

Source - See more at: http://www.stonehearthnewsletters.com/mind-body-connection-clear-new-evidence/mindfulness/#sthash.QsMH8mC0.dpuf

Fibromyalgia patients may benefit from aquatic exercise

Posted on November 3, 2014 by Stone Hearth News



Cochrane Database Syst Rev. 2014 Oct 28;10:CD011336. doi: 10.1002/14651858.CD011336. Aquatic exercise training for fibromyalgia. Bidonde J1, Busch AJ, Webber SC, Schachter CL, Danyliw A, Overend TJ, Richards RS, Rader T. Author information 1Community Health & Epidemiology, University of Saskatchewan, 107 Wiggins Rd, Saskatoon, SK, Canada, S7N 5E5.

Abstract

BACKGROUND:
Exercise training is commonly recommended for individuals with fibromyalgia. This review examined the effects of supervised group aquatic training programs (led by an instructor). We defined aquatic training as exercising in a pool while standing at waist, chest, or shoulder depth. This review is part of the update of the ‘Exercise for treating fibromyalgia syndrome’ review first published in 2002, and previously updated in 2007.

OBJECTIVES:
The objective of this systematic review was to evaluate the benefits and harms of aquatic exercise training in adults with fibromyalgia.

SEARCH METHODS: We searched The Cochrane Library 2013, Issue 2 (Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, Health Technology Assessment Database, NHS Economic Evaluation Database), MEDLINE, EMBASE, CINAHL, PEDro, Dissertation Abstracts, WHO international Clinical Trials Registry Platform, and AMED, as well as other sources (i.e., reference lists from key journals, identified articles, meta-analyses, and reviews of all types of treatment for fibromyalgia) from inception to October 2013. Using Cochrane methods, we screened citations, abstracts, and full-text articles. Subsequently, we identified aquatic exercise training studies.

SELECTION CRITERIA:
Selection criteria were: a) full-text publication of a randomized controlled trial (RCT) in adults diagnosed with fibromyalgia based on published criteria, and b) between-group data for an aquatic intervention and a control or other intervention. We excluded studies if exercise in water was less than 50% of the full intervention.

DATA COLLECTION AND ANALYSIS:
We independently assessed risk of bias and extracted data (24 outcomes), of which we designated seven as major outcomes: multidimensional function, self reported physical function, pain, stiffness, muscle strength, submaximal cardiorespiratory function, withdrawal rates and adverse effects. We resolved discordance through discussion. We evaluated interventions using mean differences (MD) or standardized mean differences (SMD) and 95% confidence intervals (95% CI). Where two or more studies provided data for an outcome, we carried out meta-analysis. In addition, we set and used a 15% threshold for calculation of clinically relevant differences.

MAIN RESULTS:

We included 16 aquatic exercise training studies (N = 881; 866 women and 15 men). Nine studies compared aquatic exercise to control, five studies compared aquatic to land-based exercise, and two compared aquatic exercise to a different aquatic exercise program.We rated the risk of bias related to random sequence generation (selection bias), incomplete outcome data (attrition bias), selective reporting (reporting bias), blinding of outcome assessors (detection bias), and other bias as low. We rated blinding of participants and personnel (selection and performance bias) and allocation concealment (selection bias) as low risk and unclear. The assessment of the evidence showed limitations related to imprecision, high statistical heterogeneity, and wide confidence intervals.

Aquatic versus control.

We found statistically significant improvements (P value < 0.05) in all of the major outcomes. Based on a 100-point scale, multidimensional function improved by six units (MD -5.97, 95% CI -9.06 to -2.88; number needed to treat (NNT) 5, 95% CI 3 to 9), self reported physical function by four units (MD -4.35, 95% CI -7.77 to -0.94; NNT 6, 95% CI 3 to 22), pain by seven units (MD -6.59, 95% CI -10.71 to -2.48; NNT 5, 95% CI 3 to 8), and stiffness by 18 units (MD -18.34, 95% CI -35.75 to -0.93; NNT 3, 95% CI 2 to 24) more in the aquatic than the control groups. The SMD for muscle strength as measured by knee extension and hand grip was 0.63 standard deviations higher compared to the control group (SMD 0.63, 95% CI 0.20 to 1.05; NNT 4, 95% CI 3 to 12) and cardiovascular submaximal function improved by 37 meters on six-minute walk test (95% CI 4.14 to 69.92). Only two major outcomes, stiffness and muscle strength, met the 15% threshold for clinical relevance (improved by 27% and 37% respectively). Withdrawals were similar in the aquatic and control groups and adverse effects were poorly reported, with no serious adverse effects reported.

Aquatic versus land-based

There were no statistically significant differences between interventions for multidimensional function, self reported physical function, pain or stiffness: 0.91 units (95% CI -4.01 to 5.83), -5.85 units (95% CI -12.33 to 0.63), -0.75 units (95% CI -10.72 to 9.23), and two units (95% CI -8.88 to 1.28) respectively (all based on a 100-point scale), or in submaximal cardiorespiratory function (three seconds on a 100-meter walk test, 95% CI -1.77 to 7.77). We found a statistically significant difference between interventions for strength, favoring land-based training (2.40 kilo pascals grip strength, 95% CI 4.52 to 0.28). None of the outcomes in the aquatic versus land comparison reached clinically relevant differences of 15%. Withdrawals were similar in the aquatic and land groups and adverse effects were poorly reported, with no serious adverse effects in either group. Aquatic versus aquatic (Ai Chi versus stretching in the water, exercise in pool water versus exercise in sea water)Among the major outcomes the only statistically significant difference between interventions was for stiffness, favoring Ai Chi (1.00 on a 100-point scale, 95% CI 0.31 to 1.69).

AUTHORS’ CONCLUSIONS:

Low to moderate quality evidence relative to control suggests that aquatic training is beneficial for improving wellness, symptoms, and fitness in adults with fibromyalgia. Very low to low quality evidence suggests that there are benefits of aquatic and land-based exercise, except in muscle strength (very low quality evidence favoring land). No serious adverse effects were reported.

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