What the experts say
Nigel Hetherington reviews the latest research material relating to coaching, exercise physiology and athletic development.
In a study exploring the relationship between coaches' behaviour and statements, and athletes' self-talk 243 athletes (106 females and 137 males) representing a variety of sports participated. Subjects completed the Athletes' Positive and Negative Self-Talk Scale, which assesses frequency of positive and negative self-talk; the Coaches' Positive and Negative Statements Scale, which assesses frequency of coaches' positive and negative statements; and the Coaching Behaviour Questionnaire, which assesses two dimensions of coaches' behaviour, supportiveness and negative activation. Structural equation modelling of the results showed that coaches' positive statements were found to mediate the relationship between coaches' supportiveness and athletes' positive self-talk. Similarly, negative statements made by the coach were found to mediate the relationship between coaches' negative activation and athletes' negative self-talk. Bottom line here is that the behaviour and statements of a coach have a direct impact on an athletes' confidence.
A study investigated adaptations in leg muscle metabolism of swimmers following a six-week, leg-kicking swimming training program. 15 male competitive swimmers were randomly assigned to an experimental group (E) or a control group (C). E performed normal leg-kicking training three times per week, whereas C performed reduced leg-kicking training (20% and 4% of weekly training distance, respectively). Before and after the training program, all swimmers performed a 200 m leg-kicking and a 400 m full-stroke freestyle time trial and a dry-land exercise test to assess peak oxygen uptake, oxygen uptake at 60W and exercise intensity at ventilatory threshold. After training, there were improvements in leg-kicking time in 200 m (-6.0s ± 2.0), oxygen uptake (-20.4 L·min-1± 3.0%) and exercise intensity at ventilatory threshold (+28.0W ± 5.0) in E swimmers, whereas time in 400 m and peak oxygen uptake remained unchanged. There were no changes in any of the measures for C swimmers. These results suggest that normal leg-kicking swimming training positively affects the conditioning of the legs, but does not improve aerobic power during the dry-land, leg-kicking exercise test or middle-distance, full-stroke, swimming performance. So, now the obvious question - why do it?
A paper examines some of research and practical issues of bicarbonate loading used to enhance both training and competitive performance. Bicarbonate loading is a popular ergogenic aid used primarily by athletes in short-duration, high-intensity sporting events and competitions. Controlled experimental trials have shown that small (worthwhile) benefits can obtained from acute doses of bicarbonate taken before exercise. However, gastrointestinal problems encountered by some athletes limit the widespread use of this practice. The transfer of positive research findings to the competitive environment has proved problematic for some individuals. More recent applications involve serial ingestion of bicarbonate over several days before competition or during high-intensity training sessions over a few weeks. The paper concludes that a number of research questions need to be addressed to enhance applications of bicarbonate loading in the elite sport environment.
The acute effects of 3 different warm-up protocols with and without a weighted vest were investigated on vertical jump (VJ) and standing long jump (LJ) performance in athletic women. Sixteen subjects participated in 3 testing sessions in random order on 3 non-consecutive days. Prior to the testing the subjects performed 1 of the following 10-minute warm-up protocols: (a) low- to moderate-intensity stationary cycling followed by 4 lower-body static stretches (SS) (3 × 20 seconds); (b) 12 moderate- to high-intensity dynamic exercises (DY); and (c) the same 12 dynamic exercises with a weighted vest (10% of body mass) worn for the last 4 exercises (DYV). Analysis of the data revealed that VJ performance was significantly greater following DYV (43.9 ± 6.7 cm) and DY (43.6 ± 6.5 cm) as compared to SS (41.7 ± 6.0 cm). Long jump performance was in the order DYV (186.8 ± 19.5 cm), DY (182.2 ± 19.1 cm) and SS (177.2 ± 18.8 cm). The authors concluded that warm-up protocols that include dynamic exercise may be a viable method of enhancing jumping performance in athletic women as compared to stationary cycling and static stretching. In addition, these data suggest that it may be desirable for athletic women to perform dynamic exercises with a weighted vest on some movements prior to the performance of the long jump.
The effectiveness of session rating of perceived exertion (RPE) to measure effort during different types of resistance training was evaluated in a study. Fifteen male subjects performed 3 different strength training protocols which all consisted of same 5 exercises but with different intensities, rest periods, and numbers of repetitions. The session RPE method (i.e. perceived exertion recorded during the session) appeared to be effective in monitoring different types of resistance training while session RPE after 30 min was a better indicator of the overall resistance sessions than average RPE. So, when you ask the question will determine the relevance of the response!
A study investigated the influence of different resistance exercise orders on the number of repetitions performed to failure and on the ratings of perceived exertion (RPE) in 23 women with a minimum of 2 years of resistance training experience. Data were collected in 2 phases: (a) 1RM determination of leg-press (LP), bench press (BP), leg extension (LE), seated machine shoulder press (SP), leg curl (LC), and seated machine triceps extension (TE); and (b) execution of 3 sets, with 2-minute rest intervals between sets and exercises, until fatigue using 80% of 1RM in 2 exercise sequences of the exact opposite order-Sequence A: BP, SP, TE, LP, LE, and LC, and Sequence B: LC, LE, LP, TE, SP, and BP. The RPE was accessed immediately after each sequence. Statistical analysis showed that RPE was not significantly different between the sequences. The mean number of repetitions per set was always less when an exercise was performed later in the exercise sequence. The data indicate that in trained women, performance of both large- and small-muscle group exercises is affected by exercise sequence.
Research compared 1RM strength, maximum power (MP), linear momentum (Mp), and the loads of 1RM responsible for maximum power (MP%) and for linear momentum (Mp%) generated in explosive concentric bench press (CBP) motion among athletes from different sports. A total of 56 athletes (13 sprinters, 16 basketball players, 16 handball players, 5 volleyball players, and 6 bodybuilders) performed CBP in the loads of 40, 50, 60, 70, and 80% of 1RM with 1-minute rest intervals. MP and Mp were assessed during CBP by customized apparatus. There were no significant differences in MP, Mp, MP%, and Mp% among the athletes. The only significant positive correlation was found between overall 1RM and Mp for athletes. In conclusion, long-term sport-specific training adaptations do not play a major role on speed-strength parameters in athletes with similar strength from different sports backgrounds. In other words a special form of strength is speed-strength and contributes to the performance of many sports.
Although research has demonstrated that isokinetic eccentric (ECC) strength is 20-60% greater than isokinetic concentric (CON) strength, few data exist comparing these strength differences in standard dynamic resistance exercises. A study determined the difference in maximal dynamic ECC and CON strength for 6 different resistance exercises in young men and women. 20 subjects who were regular exercisers with resistance training experience performed two sessions to determine CON and ECC 1 repetitions maximum for latissimus pull-down (LTP), leg press (LP), bench press (BP), leg extension (LE), seated military press (MP), and leg curl (LC) exercises. Maximal ECC and maximal CON strength were determined on weight stack machines modified to isolate ECC and CON contractions using steel bars and pulleys such that only 1 type of contraction was performed. Within 2 weeks, participants returned and completed a retest trial in a counterbalanced fashioned. Test-retest reliability was excellent for all resistance exercise trials. Men demonstrated 20-60% greater ECC than CON strength (LTP = 32%, LP = 44%, BP = 40%, LE = 35%, MP = 49%, LC = 27%). Women's strength exceeded the proposed parameters for greater ECC strength in 4 exercises, (LP = 66%, BP = 146%, MP = 161%, LC = 82%). The authors conclude that ECC/CON assessment could help coaches capitalize on muscle strength differences in young men and women during training to aid in program design and injury prevention and to enhance strength development
Eight men and 6 women of the Australian Institute of Sport Road Cycling squads participated in a study to quantify the fluid and food consumed during a professional road-cycling tour. The men competed in the 6-d Tour Down Under (Adelaide, Australia), and the women, in the 10-d Tour De L'Aude (Aude, France). Body mass was recorded before and immediately after the race. Cyclists recalled the number of water bottles and amount of food they had consumed. Men and women recorded body-mass losses of ~2 kg (2.8% body mass) and 1.5 kg (2.6% body mass), respectively, per stage during the long road races. Men had an average fluid intake of 1.0 L/h, whereas women only consumed on average 0.4 L/h. In addition, men consumed CHO at the rate suggested by dietitians (average CHO intake of 48 g/h), but again the women failed to reach recommendations, with an average intake of ~21 g/h during a road stage. Men appeared to drink and eat during racing in accordance with current nutritional recommendations, but women failed to reach these guidelines. Both men and women finished their races with a body-mass loss of ~2.6% to 2.8%. Question is - just how do women do it?
Caffeine is regarded as a diuretic despite evidence that hydration is not impaired with habitual ingestion. A study aimed to determine whether a caffeinated sports drink impairs fluid delivery and hydration during exercise in warm, humid conditions (28.5 °C, 60% relative humidity). Sixteen cyclists completed 3 trials: placebo (P), carbohydrate-electrolyte (CE), and caffeinated (195 mg/L) sports drink (CAF+CE). Subjects cycled for 120 min at 60-75% VO2max followed by 15 min of maximal-effort cycling. Heart rate and rectal temperature were similar until the final 15 min, when these responses and exercise intensity were higher with CAF+CE than with CE and P. Sweat rate, urine output, plasma- volume losses, serum electrolytes, and blood deuterium-oxide accumulation were not different. Serum osmolality was higher with CAF+CE vs. P but not CE. The authors concluded that CAF+CE appears as rapidly in blood as CE and maintains hydration and sustains cardiovascular and thermoregulatory function as well as CE during exercise in a warm, humid environment. You pay your money and you take your choice!
This study compared 3d of carbohydrate loading (CHOL; 8.4 g·kg-1·d-1 carbohydrate) in female eumenorrheic athletes with 3d of an isoenergetic normal diet (NORM; 5.2 g·kg-1·d-1 carbohydrate) and examined the effect of menstrual-cycle phase on performance, muscle-glycogen concentration [glyc], and substrate utilization. Nine moderately trained eumenorrheic women cycled in an intermittent protocol varying in intensity from 45% to 75% VO2max for 75 min, followed by a 16-km time trial at the midfollicular (MF) and midluteal (ML) phases of the menstrual cycle on NORM and CHOL. Time-trial performance was not affected by diet (CHOL 26.10 ± 1.04 min, NORM 26.16 ± 1.35 min) or menstrual-cycle phase (MF 26.05 ± 1.10 min, ML 26.23 ± 1.33 min). Resting [glyc] was lowest in the MF phase after NORM (575 ± 145 mmol·kg-1·dw-1), compared with the MF phase after CHOL (728 mmol·kg-1·dw-1) and the ML phase after CHOL and NORM (756 and 771 mmol·kg-1·dw-1, respectively). No effect of phase on substrate utilization during exercise was observed. These data support previous observations of greater resting [glyc] in the ML than the MF phase of the menstrual cycle and suggest that lower glycogen storage in the MF phase can be overcome by carbohydrate loading.
A revealing study aimed to describe and compare training characteristics of the 2004 U.S. Olympic Marathon Trials qualifiers. 104 men and 151 women received questionnaires. 93 (37 men, 56 women) responded and were categorized as elite (men <2 hours 15 min, women <2 hours 40 min) or national class. Analysis of the data showed that men and women ran 75% and 68% of their weekly training distance, respectively, below marathon race pace. Men trained longer than women (12.2 ± 5.3 vs 8.8 ± 5.6 years), ran more often (8.7 ± 2.8 vs 7.1 ± 2.5 times/wk), and ran farther (145.3 ± 25.6 vs 116.0 ± 26.5 km/wk). Elite women ran more than national-class women (135.8 ± 31.5 vs 111.3 ± 23.3 km/wk). Distances run at specific intensities were similar between sexes. For men and women, respectively, 49% and 31% did not have a coach and 65% and 68% trained alone. Marathon performance correlated to 5-km, 10-km, and half-marathon performance and to years training, average and peak weekly distance, number of weekly runs, and number of runs over 32 km for women. Among U.S. Olympic Marathon Trials qualifiers, there is no consensus as to how to prepare for the marathon beyond running at a pace slower than race pace. Weekly training distance seems to influence women's marathon performance more than it does men's. Because many of these athletes train alone and without a coach, further research is warranted on the reasons that these athletes train the way they do.
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About the Author
Nigel Hetherington is the Head Track & Field Coach at the internationally acclaimed Singapore Sports School. He is a former National Performance Development Manager for Scottish Athletics and National Sprints Coach for Wales. Qualified and highly active as a UK Athletics (UKA) level 4 performance coach in all events he has coached athletes to National and International honours in sprints, hurdles as well as a World Record holder in the Paralympic shot. He has 10 years experience as senior coach educator and assessor trainer on behalf of UKA. Nigel is also an experienced athlete in sprint (World Masters Championship level) and endurance (3-hour marathon runner plus completed the 24 hour 'Bob Graham Round' ultra-endurance event up and down 42 mountain peaks in the English Lake District). He is a chartered chemist with 26 years' experience in scientific research and publishing.
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