Resumos selecionados em Ciências do Esporte

J Strength Cond Res. 2011 Mar;25(3):668-82.
Strength and conditioning practices in rowing.
Gee TI, Olsen PD, Berger NJ, Golby J, Thompson KG.

There is limited published research on the practices of strength and conditioning
(S &C) coaches in Great Britain. Information about training program design would
be useful in developing models of good practice and ecologically valid
intervention studies. The aim of this research was to quantify the training
practices of coaches responsible for the S&C of rowing athletes. A questionnaire
was developed that consisted of 6 sections: (a) personal details, (b) physical
testing, (c) strength and power development, (d) flexibility development, (e)
unique aspects of the program, and (f) any further relevant comments regarding
the athletes prescribed training program. Twenty-two rowing and 10 S&C coaches
with an average of 10.5 ± 7.2 years’ experience agreed to complete the
questionnaire. Approximately, 34% coached rowers of Olympic standard, 34% coached
national standard, 3% coached regional standard, 19% coached club standard, and
10% coached university standard rowers. All coaches agreed that strength training
enhanced rowing performance and the majority (74%) indicated that athletes’
strength trained 2-3 times a week. Almost all coaches (94%) reported their rowers
performed strength training, with 81% using Olympic lifting, and 91% employing a
periodized training model. The clean (63%) and squat (27%) were rated the most
important prescribed exercises. Approximately 50% of coaches used plyometrics
such as depth jumps, box drills, and standing jumps. Ninety-four percent
indicated they conducted physical testing on their rowers, typically assessing
cardiovascular endurance (80%), muscular power (70%), muscular strength (70%),
and anaerobic capacity (57%). This research represents the only published survey
to date on the S&C practices in rowing within Great Britain.

J Sports Sci. 2011 Mar;29(6):555-61.
Exercise intensity optimization for men with high cardiorespiratory fitness.
Azevedo LF, Perlingeiro PS, Brum PC, Braga AM, Negrão CE, de Matos LD.

Exercise intensity is a key parameter for exercise prescription but the optimal
range for individuals with high cardiorespiratory fitness is unknown. The aims of
this study were (1) to determine optimal heart rate ranges for men with high
cardiorespiratory fitness based on percentages of maximal oxygen consumption
(%VO(2max)) and reserve oxygen consumption (%VO(2reserve)) corresponding to the
ventilatory threshold and respiratory compensation point, and (2) to verify the
effect of advancing age on the exercise intensities. Maximal cardiorespiratory
testing was performed on 210 trained men. Linear regression equations were
calculated using paired data points between percentage of maximal heart rate
(%HR(max)) and %VO(2max) and between percentage of heart rate reserve (%HRR) and
%VO(2reserve) attained at each minute during the test. Values of %VO(2max) and
%VO(2reserve) at the ventilatory threshold and respiratory compensation point
were used to calculate the corresponding values of %HR(max) and %HRR,
respectively. The ranges of exercise intensity in relation to the ventilatory
threshold and respiratory compensation point were achieved at 78-93% of HR(max)
and 70-93% of HRR, respectively. Although absolute heart rate decreased with
advancing age, there were no age-related differences in %HR(max) and %HRR at the
ventilatory thresholds. Thus, in men with high cardiorespiratory fitness, the
ranges of exercise intensity based on %HR(max) and %HRR regarding ventilatory
threshold were 78-93% and 70-93% respectively, and were not influenced by
advancing age.

Sports Med. 2011 Mar 1;41(3):199-220. doi: 10.2165/11539740-000000000-00000.
Physiology of small-sided games training in football: a systematic review.
Hill-Haas SV, Dawson B, Impellizzeri FM, Coutts AJ.

Small-sided games (SSGs) are played on reduced pitch areas, often using modified
rules and involving a smaller number of players than traditional football. These
games are less structured than traditional fitness training methods but are very
popular training drills for players of all ages and levels. At present, there is
relatively little information regarding how SSGs can best be used to improve
physical capacities and technical or tactical skills in footballers. However,
many prescriptive variables controlled by the coach can influence the exercise
intensity during SSGs. Coaches usually attempt to change the training stimulus in
SSGs through altering the pitch area, player number, coach encouragement,
training regimen (continuous vs interval training), rules and the use of
goalkeepers. In general, it appears that SSG exercise intensity is increased with
the concurrent reduction in player number and increase in relative pitch area per
player. However, the inverse relationship between the number of players in each
SSG and exercise intensity does not apply to the time-motion characteristics.
Consistent coach encouragement can also increase training intensity, but most
rule changes do not appear to strongly affect exercise intensity. The variation
of exercise intensity measures are lower in smaller game formats (e.g. three vs
three) and have acceptable reproducibility when the same game is repeated between
different training sessions or within the same session. The variation in exercise
intensity during SSGs can also be improved with consistent coach encouragement
but it is still more variable than traditional generic training methods. Other
studies have also shown that SSGs containing fewer players can exceed match
intensity and elicit similar intensities to both long- and short-duration
high-intensity interval running. It also appears that fitness and
football-specific performance can be improved equally with SSG and generic
training drills. Future research is required to examine the optimal periodization
strategies of SSGs training for the long-term development of physiological
capacity, technical skill and tactical proficiency.

Gait Posture. 2011 Mar;33(3):466-72. Epub 2011 Jan 20.
Changes in balance, functional performance and fall risk following whole body
vibration training and vitamin D supplementation in institutionalized elderly
women. A 6 month randomized controlled trial.
Bogaerts A, Delecluse C, Boonen S, Claessens AL, Milisen K, Verschueren SM.

Falls in the elderly constitute a growing public health problem. This randomized
controlled trial investigated the potential benefit of 6 months of whole body
vibration (WBV) training and/or vitamin D supplementation on balance,
functionality and estimated fall risk in institutionalized elderly women. A total
of 113 women (mean age: 79.6) were randomly assigned to either a WBV or a
no-training group, receiving either a conventional dose (880 IU/d) or a high dose
(1600 IU/d) of vitamin D3. The WBV group performed exercises on a vibration
platform 3×/week. Balance was evaluated by computerized posturography.
Functionality was assessed by 10 m walk test, Timed up and Go (TUG) performance
and endurance capacity (Shuttle Walk). Fall risk was determined with the
Physiological Profile Assessment. Performance on the 10 m walk test and on TUG
improved over time in all groups. For none of the parameters, high-dose vitamin D
resulted in a better performance than conventional dosing. The improvements in
the WBV group in endurance capacity, walking at preferred speed, and TUG were
significantly larger than the changes with supplementation alone. No additional
benefit of WBV training could be detected on fall risk and postural control,
although sway velocity and maximal isometric knee extension strength improved
only in the WBV group. This trial showed that a high-dose vitamin D
supplementation is not more efficient than conventional dosing in improving
functionality in institutionalized elderly. WBV training on top of vitamin D
supplementation provided an added benefit with regard to walking, TUG
performance, and endurance capacity.

Acta Paediatr. 2011 Apr;100(4):565-9. doi: 10.1111/j.1651-2227.2010.02135.x.
Cross-sectional trends in cardiovascular fitness in Swedish 16-year-olds between
1987 and 2007.
Ekblom AB, Bak EA, Ekblom BT.

AIM: We sought to investigate the temporal trends in estimated maximal aerobic
capacity in adolescents (mean age 16.1).
METHODS: Analyses were based on data from three population-based samples,
collected in 1987 (n=221), 2001 (n=537) and 2007 (n=265). Subjects underwent
sub-maximal ergometer testing. Absolute and relative aerobic capacities were
estimated using the Åstrand-Ryhming nomogram.
RESULTS: Compared to 1987, values for estimated relative and absolute maximal
aerobic capacities were lower in 2001 and 2007, and values in 2007 were lower
compared to 2001, in both boys and girls, except for absolute capacity between
1987 and 2001 in girls. The differences over time did not differ between genders.
Absolute values changed from 3.0 and 2.5 L/min in 1987 to 2.5 and 2.2 L/min in
2007, for boys and girls, respectively. Relative values changed from 46.5 and
45.9 mL/min/kg in 1987 to 35.0 and 36.6 mL/min/kg, in 2007, for boys and girls,
respectively.
CONCLUSION: Based on earlier reports on the relationship between aerobic capacity
and metabolic risk, the results from the present study provide argument that
future public health will be affected negatively.

Med Sci Sports Exerc. 2010 Dec;42(12):2231-6.
Time trends in physical activity in the state of São Paulo, Brazil: 2002-2008.
Matsudo VK, Matsudo SM, Araújo TL, Andrade DR, Oliveira LC, Hallal PC.

PURPOSE: To document time trends in physical activity in the state of São Paulo,
Brazil (2002-2008). In addition, we discuss the role of Agita São Paulo at
explaining such trends.
METHODS: Cross-sectional surveys were carried out in 2002, 2003, 2006, and 2008
in the state of São Paulo, Brazil, using comparable sampling approaches and
similar sample sizes. In all surveys, physical activity was measured using the
short version of the International Physical Activity Questionnaire. Separate
weekly scores of walking and moderate- and vigorous-intensity physical activities
were generated; cutoff points of 0 and 150 min·wk were used. Also, we created a
total physical activity score by summing these three types of activity. We used
logistic regression models for adjusting time trends for the different
sociodemographic compositions of the samples.
RESULTS: The prevalence of no physical activity decreased from 9.6% in 2002 to
2.7% in 2008, whereas the proportion of subjects below the 150-min threshold
decreased from 43.7% in 2002 to 11.6% in 2008. These trends were mainly explained
by increases in walking and moderate-intensity physical activity. Increases in
physical activity were slightly greater among females than among males. Logistic
regression models confirmed that these trends were not due to the different
compositions of the samples.
CONCLUSIONS: Physical activity levels are increasing in the state of São Paulo,
Brazil. Considering that the few data available in Brazil using the same
instrument indicate exactly the opposite trend and that Agita São Paulo primarily
incentives the involvement in moderate-intensity physical activity and walking,
it seems that at least part of the trends described here are explained by the
Agita São Paulo program.

Eur J Appl Physiol. 2011 Jul 14. [Epub ahead of print]
Similar increases in muscle size and strength in young men after training with
maximal shortening or lengthening contractions when matched for total work.
Moore DR, Young M, Phillips SM.

Training exclusively with eccentric (lengthening) contractions can result in
greater muscular adaptations than training with concentric (shortening)
contractions. We aimed to determine whether training-induced increases in muscle
size and strength differed between muscles performing maximal lengthening (LC) or
maximal shortening (SC) contractions when total external work is equivalent. Nine
healthy young males completed a 9-week isokinetic (0.79Â rad/s) resistance
training program of the elbow flexors whereby they performed LC with one arm and
an equivalent volume of total external work with the contralateral arm as SC.
Training increased isometric peak torque for both LC (~10%) and SC (~20%) with no
difference (PÂ =Â 0.14) between conditions. There were also similar increases in
isokinetic peak torque at both slow (0.79Â rad/s) and fast (5.24Â rad/s) shortening
and lengthening peak torque for both LC (~8-10%) and SC (~9-20%). Training
increased work per repetition similarly for both LC (~17%) and SC (~22%), in
spite of ~40% greater work per repetition with LC. The increase in muscle
cross-sectional area with training was also similar (PÂ =Â 0.37) between LC (~6.5%)
and SC (~4.6%). We conclude that increases in muscle size and strength with
short-term unilateral resistance training are unrelated to muscle contraction
type when matched for both exercise intensity (i.e. maximal contractions) and
total external work.

Clin Interv Aging. 2011;6:141-9. Epub 2011 Jun 15.
Effects of a weight loss plus exercise program on physical function in
overweight, older women: a randomized controlled trial.
Anton SD, Manini TM, Milsom VA, Dubyak P, Cesari M, Cheng J, Daniels MJ, Marsiske
M, Pahor M, Leeuwenburgh C, Perri MG.

BACKGROUND: Obesity and a sedentary lifestyle are associated with physical
impairments and biologic changes in older adults. Weight loss combined with
exercise may reduce inflammation and improve physical functioning in overweight,
sedentary, older adults. This study tested whether a weight loss program combined
with moderate exercise could improve physical function in obese, older adult
women.
METHODS: Participants (N = 34) were generally healthy, obese, older adult women
(age range 55-79 years) with mild to moderate physical impairments (ie,
functional limitations). Participants were randomly assigned to one of two groups
for 24 weeks: (i) weight loss plus exercise (WL+E; n = 17; mean age = 63.7 years
[4.5]) or (ii) educational control (n = 17; mean age = 63.7 [6.7]). In the WL+E
group, participants attended a group-based weight management session plus three
supervised exercise sessions within their community each week. During exercise
sessions, participants engaged in brisk walking and lower-body resistance
training of moderate intensity. Participants in the educational control group
attended monthly health education lectures on topics relevant to older adults.
Outcomes were: (i) body weight, (ii) walking speed (assessed by 400-meter walk
test), (iii) the Short Physical Performance Battery (SPPB), and (iv) knee
extension isokinetic strength.
RESULTS: Participants randomized to the WL+E group lost significantly more weight
than participants in the educational control group (5.95 [0.992] vs 0.23 [0.99]
kg; P < 0.01). Additionally, the walking speed of participants in the WL+E group
significantly increased compared with that of the control group (reduction in
time on the 400-meter walk test = 44 seconds; P < 0.05). Scores on the SPPB
improved in both the intervention and educational control groups from pre- to
post-test (P < 0.05), with significant differences between groups (P = 0.02).
Knee extension strength was maintained in both groups.
CONCLUSION: Our findings suggest that a lifestyle-based weight loss program
consisting of moderate caloric restriction plus moderate exercise can produce
significant weight loss and improve physical function while maintaining muscle
strength in obese, older adult women with mild to moderate physical impairments.

J Strength Cond Res. 2011 Jul 8. [Epub ahead of print]
Does Cluster Loading Enhance Lower Body Power Development in Preseason
Preparation of Elite Rugby Union Players?
Hansen KT, Cronin JB, Pickering SL, Newton MJ.

Hansen, KT, Cronin, JB, Pickering, SL, Newton, MJ. Does cluster loading enhance
lower body power development in preseason preparation of elite rugby union
players? J Strength Cond Res 25(X): 000-000, 2011-The purpose of this study was
to ascertain whether cluster training led to improved power training adaptations
in the preseason preparation of elite level rugby union players. Eighteen highly
trained athletes were divided into 2 training groups, a traditional training (TT,
N = 9) group and a cluster training (CT, N = 9) group before undertaking 8 weeks
of lower body resistance training. Force-velocity-power profiling in the jump
squat movement was undertaken, and maximum strength was assessed in the back
squat before and after the training intervention. Two-way analysis of variance
and magnitude-based inferences were used to assess changes in maximum strength
and force, velocity, and power values pretraining to posttraining. Both TT and CT
groups significantly (p < 0.05) increased maximum strength posttraining. There
was a possibly negative effect for the CT group on maximum strength when compared
with that for the TT group (pretraining to posttraining change = 14.6 ± 18.0 and
18.3 ± 10.1%, respectively). There were no significant differences pretraining to
posttraining for any jump squat force, velocity, or power measures. However,
magnitude-based inferences showed that there was a likely positive effect of CT
when compared with that of TT for peak power (pretraining to posttraining change
= 7.5 ± 7.0 and 1.0 ± 6.2%, respectively) and peak velocity at 40 kg (pretraining
to posttraining change = 4.7 ± 6.1 and 0.0 ± 5.0%, respectively) and for peak
velocity at body weight (pretraining to posttraining change = 3.8 ± 3.4 and 0.5 ±
3.8%, respectively). Although both a traditional and cluster training loading
pattern improved lower body maximum strength in a highly trained population, the
traditional training structure resulted in greater maximum strength adaptation.
There was some evidence to support the possible benefit of cluster type loading
in training prescription for lower body power development.

Am J Cardiol. 2011 Jul 7. [Epub ahead of print]
Comparison of Aerobic Versus Resistance Exercise Training Effects on Metabolic
Syndrome (from the Studies of a Targeted Risk Reduction Intervention Through
Defined Exercise – STRRIDE-AT/RT).
Bateman LA, Slentz CA, Willis LH, Shields AT, Piner LW, Bales CW, Houmard JA,
Kraus WE.

Aerobic training (AT) improves the metabolic syndrome (MS) and its component risk
factors; however, to our knowledge, no randomized clinical studies have addressed
whether resistance training (RT) improves the MS when performed alone or combined
with AT. Sedentary, overweight dyslipidemic men and women, aged 18 to 70 years
completed a 4-month inactive run-in period and were randomized to 1 of 3
eight-month exercise programs (n = 196). The exercise programs were (1) RT (3
days/week, 3 sets/day of 8 to 12 repetitions of 8 different exercises targeting
all major muscle groups); (2) AT (∼120 minutes/week at 75% of the maximum oxygen
uptake), and (3) AT and RT combined (AT/RT) (exact combination of AT and RT). Of
the 196 randomized patients, 144 completed 1 of the 3 exercise programs. The 86
participants with complete data for all 5 MS criteria were used in the present
analysis, and a continuous MS z score was calculated. Eight months of RT did not
change the MS score. AT improved the MS score (p <0.07) and showed a trend toward
significance compared to RT (p <0.10). AT/RT significantly decreased the MS score
and was significantly different from RT alone. In conclusion, RT was not
effective at improving the MS score; however, AT was effective. Combined AT and
RT was similarly effective but not different from AT alone. When weighing the
time commitment versus health benefit, the data suggest that AT alone was the
most efficient mode of exercise for improving cardiometabolic health.

Neurobiol Aging. 2011 Jul 6. [Epub ahead of print]
Resistance training and functional plasticity of the aging brain: a 12-month
randomized controlled trial.
Liu-Ambrose T, Nagamatsu LS, Voss MW, Khan KM, Handy TC.

Maintaining functional plasticity of the cortex is essential for healthy aging
and aerobic exercise may be an effective behavioral intervention to promote
functional plasticity among seniors. Whether resistance training has similar
benefits on functional plasticity in seniors has received little investigation.
Here we show that 12 months of twice-weekly resistance training led to functional
changes in 2 regions of cortex previously associated with response inhibition
processes-the anterior portion of the left middle temporal gyrus and the left
anterior insula extending into lateral orbital frontal cortex-in
community-dwelling senior women. These hemodynamic effects co-occurred with
improved task performance. Our data suggest that resistance training improved
flanker task performance in 2 ways: (1) an increased engagement of response
inhibition processes when needed; and (2) a decreased tendency to prepare
response inhibition as a default state. However, we highlight that this effect of
resistance training was only observed among those who trained twice weekly;
participants of the once-weekly resistance training did not demonstrate
comparable response profiles, both in behavioral performance and hemodynamic
activity in cortex. In sum, our findings suggest that twice-weekly resistance
training in seniors can positively impact functional plasticity of response
inhibition processes in cortex, and that it does so in a manner that complements
the effects on selective attention that have previously been ascribed to aerobic
exercise in seniors.

Acta Physiol Hung. 2011 Jun;98(2):128-36.
Exercise training biomarkers: influence of short-term diet modification on the
blood lactate to rating of perceived exertion (La:RPE) ratio.
Duke JW, Lane AR, Behr MB, Ondrak KS, Hackney AC.

This study examined the effect of dietary consumption of carbohydrates (CHO) on
the blood lactate to rating of perceived exertion (La:RPE) ratio during an
intense micro-cycle of exercise training. This ratio is a proposed biomarker of
exercise training stress and potential indicator for under- or overtraining in
athletes. Sixteen male athletes were randomly assigned into two groups; high CHO
(H-CHO; 60% of daily caloric intake) and low CHO (L-CHO; 30% of daily caloric
intake). Diets were controlled the day before and for the three days of the
micro-cycle. The micro-cycle consisted of three successive days of 60 minutes of
intense cycling (∼70% of VO2peak). Blood samples were obtained immediately before
and after exercise (post) on each day of exercise training (D1, D2, D3) and were
analyzed for blood lactate. Rating of perceived exertion (RPE) scores were taken
at the end of each exercise session and combined with the post exercise lactate
value to form the La:RPE ratio. An analysis of variance (ANOVA) showed a
significant difference between the La:RPE ratio for the H-CHO and L-CHO groups at
D3 even though the exercise intensity was not significantly different between the
groups. Specifically, the ratio was significantly (p < 0.02) lower on D3 in the
L-CHO group (∼31% lower) than in the H-CHO group. From these findings it is
recommended that diet needs to be monitored when using the La:RPE ratio as an
exercise training biomarker to determine whether an athlete is truly
under-training or overtraining. Athletes or coaches that use the La:RPE ratio as
a training biomarker, but do not monitor dietary CHO intake need to interpreted
their findings carefully.

J Strength Cond Res. 2011 Mar;25(3):767-77.
Recovery after heavy resistance exercise and skeletal muscle androgen receptor
and insulin-like growth factor-I isoform expression in strength trained men.
Ahtiainen JP, Lehti M, Hulmi JJ, Kraemer WJ, Alen M, Nyman K, Selanne H,
Pakarinen A, Komulainen J, Kovanen V, Mero AA, Hakkinen K.

The effects of heavy resistance exercise on skeletal muscle androgen receptor
(AR) protein concentration and mRNAs of AR, insulin-like growth factor-I
(IGF)-IEa, and mechano growth factor (MGF) expression were examined from biopsies
of vastus lateralis (VL) muscle before and 48 hours after heavy resistance
exercise (5 × 10 repetition maximum [RM] leg press and 4 × 10RM squats) in 8
adult strength trained men. The present exercise induced an acute decrease in
maximal isometric force and increased serum total testosterone (T) and free
testosterone (FT) concentrations. During 2 recovery days, maximal isometric force
and subjective perception of physical fitness remained significantly lowered,
whereas serum creatine kinase activity, subjective muscle soreness, and muscle
swelling (i.e., thickness of VL by ultrasound) were significantly increased
compared to pre-exercise values. Subjective perception of physical fitness was
followed up to 7 days, and by 6 days postexercise, it was elevated above the
pre-exercise level. Basal T and FT concentrations remained unaltered after the
exercise. No statistically significant changes were observed in AR protein or
mRNA expression, but IGF-IEa (p < 0.05) and MGF (p < 0.05) mRNA expression were
increased compared to pre-exercise levels. These findings indicate that IGF-IEa
and MGF responses may be related to acute regenerative processes in muscle
because of exercise and may contribute to muscular adaptation to resistance
exercise. Subjective perception of physical fitness suggests that recovery over a
pre-exercise level of the present type of heavy resistance exercise can take
approximately 6 days.

Anúncios

Deixe um comentário

Preencha os seus dados abaixo ou clique em um ícone para log in:

Logotipo do WordPress.com

Você está comentando utilizando sua conta WordPress.com. Sair / Alterar )

Imagem do Twitter

Você está comentando utilizando sua conta Twitter. Sair / Alterar )

Foto do Facebook

Você está comentando utilizando sua conta Facebook. Sair / Alterar )

Foto do Google+

Você está comentando utilizando sua conta Google+. Sair / Alterar )

Conectando a %s