Assisted and resisted sprint training in swimming

This study was undertaken to determine whether the resisted-sprint in overstrength (OSt) or the assisted-sprint in overspeed (OSp) could be efficient training methods to increase 100-m front crawl performance. Thirty-seven (16 men, 21 women) competition-level swimmers (mean +/- SD: age 17.5 +/- 3.5 years, height 173 +/- 14 cm, weight 63 +/- 14 kg) were randomly divided into 3 groups: OSt, OSp, and control (C). All swimmers trained 6 days per week for 3 weeks, including 3 resisted or assisted training sessions per week for the groups OSt and OSp respectively. Elastic tubes were used to generate swimming overstrength and overspeed. Three 100-m events were performed before, during, and after the training period. Before each 100-m event, strength of the elbow flexors and extensors was measured with an isokinetic dynamometer. Stroke rate and stroke length were evaluated using the video-recorded 100-m events. In the OSt group, elbow extensor strength, swimming velocity, and stroke rate significantly increased (p < 0.05), while stroke length remained unchanged after the 3-week training period. In the OSp group, stroke rate significantly increased (p < 0.05) and stroke length significantly decreased (p < 0.05) without changes in swimming velocity. No significant variations in the C group were observed. Both OSt and OSp proved to be more efficient than the traditional training program. However, the OSt training program had a larger impact on muscle strength, swimming performance, and stroke technique than the OSp program.     

Dry-land strength training vs. electrical stimulation in sprint swimming performance

This study was undertaken to compare the effects of dry-land strength training vs. an electrical stimulation program on swimmers. Twenty-four national-level swimmers were randomly assigned to 3 groups: the dry-land strength training program (S), the electrical stimulation training program (ES), and the control (C) group. The training program lasted 4 weeks. The subjects were evaluated before the training, at the end of the training program, and 4 weeks later. The outcome values ascertained were peak torque during arm extension at different velocities (from -60 to 180°·s(-1)) using an isokinetic dynamometer and performance, stroke rate, and stroke length during a 50-m front crawl. A significant increase in swimming velocity and peak torque was observed for both S and ES at the end of the training and 4 weeks later. Stroke length increased in the S group but not in the ES group. However, no significant differences in swimming velocity between S and ES groups were observed. No significant changes occurred in the C group. Programs combining swimming training with dry-land strength or electrical stimulation programs led to a similar gain in sprint performance and were more efficient than swimming alone.     

Effects of dry-land vs. resisted- and assisted-sprint exercises on swimming sprint performances

This study was undertaken to compare the effects of dry-land strength training with a combined in-water resisted- and assisted-sprint program in swimmer athletes. Twenty-one swimmers from regional to national level participated in this study. They were randomly assigned to 3 groups: the strength (S) group that was involved in a dry-land strength training program where barbells were used, the resisted- and assisted-sprint (RAS) group that got involved in a specific water training program where elastic tubes were used to generate resistance and assistance while swimming, and the control (C) group which was involved in an aerobic cycling program. During 12 weeks, the athletes performed 6 training sessions per week on separate days. All of them combined the same aerobic dominant work for their basic training in swimming and running with their specific training. Athletes were evaluated 3 times: before the training program started, after 6 weeks of training, and at the end of the training program. The outcome values were the strength of the elbow flexors and extensors evaluated using an isokinetic dynamometer, and the speed, stroke rate, stroke length, and stroke depth observed during a 50-meter sprint. No changes were observed after 6 weeks of training. At the end of the training period, we observed significant increases in swimming velocity, and strength of elbow flexors and extensors both in the S and RAS groups. However, stroke depth decreased both in the S and RAS groups. Stroke rate increased in the RAS but not in the S group. However, no significant differences in the swimming performances between the S and RAS groups were observed. No significant changes occurred in C. Altogether, programs combining swimming with dry-land strength or with in-water resisted- and assisted-sprint exercises led to a similar gain in sprint performance and are more efficient than traditional swimming training methods alone.     

Effects of in-season strength maintenance training frequency in professional soccer players

The aim of the present study was to examine the effect of in-season strength maintenance training frequency on strength, jump height, and 40-m sprint performance in professional soccer players. The players performed the same strength training program twice a week during a 10-week preparatory period. In-season, one group of players performed 1 strength maintenance training session per week (group 2 + 1; n = 7), whereas the other group performed 1 session every second week (group 2 + 0.5; n = 7). Only the strength training frequency during the in-season differed between the groups, whereas the exercise, sets and number of repetition maximum as well as soccer sessions were similar in the 2 groups. The preseason strength training resulted in an increased strength, sprint, and jump height (p < 0.05). During the first 12 weeks of the in-season, the initial gain in strength and 40-m sprint performance was maintained in group 2 + 1, whereas both strength and sprint performance were reduced in group 2 + 0.5 (p < 0.05). There was no statistical significant change in jump height in any of the 2 groups during the first 12 weeks of the in-season. In conclusion, performing 1 weekly strength maintenance session during the first 12 weeks of the in-season allowed professional soccer players to maintain the improved strength, sprint, and jump performance achieved during a preceding 10-week preparatory period. On the other hand, performing only 1 strength maintenance session every second week during the in-season resulted in reduced leg strength and 40-m sprint performance. The practical recommendation from the present study is that during a 12-week period, 1 strength maintenance session per week may be sufficient to maintain initial gain in strength and sprint performance achieved during a preceding preparatory period.     

Influence of short vs. long repetition sprint training on selected fitness components in young soccer players

The aim of this study was to compare the effect of short-sprint repetition and long-sprint repetition training (SST, LST), matched for total distance, on selected fitness components in young soccer players. Thirty young (14-15 years) soccer players were randomly assigned to either the short-sprint training group or long-sprint training group and completed 2 similar sets of fitness tests before and after 7 weeks of training. The 2 training programs consisted of SST (4-6 sets of 4 × 50-m all-out sprint) and LST (4-6 sets of 200-m run at 85% of maximum speed), each performed 3 times a week. Before training, there were no baseline between-group differences in predicted VO2max, standing long jump, 30-m sprint time, 4 × 10-m shuttle running time, and 250-m running time. Both training programs led to a significant improvement in VO2max (predicted from the 20-m shuttle run, p < 0.01), with no between-group difference (p = 0.14). Both training programs also led to a significant improvement in the anaerobic fitness variables of 30-m sprint time (p < 0.01), 4 × 10-m shuttle running time (p < 0.01), and 250-m running time (p < 0.01), with no between-group differences. Neither of the training programs had a significant effect on standing long jump (p = 0.21). The study showed that long, near-maximal sprints, and short, all-out sprint training, matched for total distance, are equally effective in enhancing both the aerobic and anaerobic fitness of young soccer players. Therefore, to maintain a player's training interest and enthusiasm, coaches may alternate between these methods during the busy soccer season.     

Lactate threshold and performance adaptations to 4 weeks of training in untrained swimmers: volume vs. intensity

The purpose of this study was to investigate the impact of 4 weeks of high-intensity vs. high-volume swim training on lactate threshold (LT) characteristics and performance. Thirteen untrained swimmers with a mean age of 19.0 ± 0.5 undertook an incremental swimming test before and after 4 weeks of training for the determination of LT. Performance was evaluated by a 50-m maximum freestyle test. The swimmers were assigned to 1 of each of 2 training groups. The high-intensity group (n = 6) focused on sprint training (SP) and swam a total of 1,808 ± 210 m. The high-volume group (n = 7) followed the same program as the SP group but swam an additional 1,100 m (38% more) of endurance swimming (SP + End). A training effect was evident in both groups as seen by the similar improvements in sprint performance of the 50-m maximum time (p < 0.01), peak velocity increases and the lower value of lactate at the individual LTs (p < 0.01). Lactate threshold velocity improved only in the SP + End group from 1.20 ± 0.12 m·s(-1) pretraining to 1.32 ± 0.12 m·s(-1) posttraining (p = 0.77, effect size = 1, p < 0.01), expressed by the rightward shifts of the individual lactate-velocity curves, indicating an improvement in the aerobic capacity. Peak lactate and lactate concentrations at LT did not significantly change. In conclusion, this study was able to demonstrate that 4 weeks of either high-intensity or high-volume training was able to demonstrate similar improvements in swimming performance. In the case of lack of significant changes in lactate profiling in response to high-intensity training, we could suggest a dissociation between the 2.     

The effects of athletic training and muscle contractile character on the pressor response to isometric exercise of the human triceps surae

In this study, the influence of athletic training status and the contractile character of the active muscle on the magnitude of the pressor response (PR) to voluntary and electrically evoked isometric plantar flexion was investigated. Subjects were 10 sprint-trained athletes (sprint) (100-m, 200-m and 400-m) [mean (SD) age, 21 (2) years], 14 endurance trained athletes (distance) [22 (2) years] and 8 untrained men (control) [23 (3) years]. Twitch time to peak tension (TPT) in the sprint group [108 (7) ms] was significantly less (P<0.001) than that of the distance group [124 (10) ms]. During voluntary contraction, the mean change in systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (fc) was not significantly different between groups. During electrically evoked contractions, mean changes in SBP, DBP and fc were not significantly different between the sprint, distance and control groups. However, division of the sprint group into 400-m (sprint I) and 100/200-m athletes (sprint II) showed that an increase in DBP of 1.6 kPa (12 mm Hg) in sprint I was significantly less (P<0.05) than the 2.5 kPa (19 mm Hg) increase observed for both the distance and control groups. Prediction of the DBP response from our previously published relationship between TPT and DBP showed close agreement in all subject groups except sprint I; in these subjects the observed DBP response was only 55% of that predicted. Attenuation of the PR in the involuntary experiment suggests that some aspect of sprint training, but not endurance training, modifies the muscle afferent input to the PR in man.     

Effect of velocity and added resistance on selected coordination and force parameters in front crawl

The effect of (a) increasing velocity and (b) added resistance was examined on the stroke (stroke length, stroke rate [SR]), coordination (index of coordination [IdC], propulsive phases), and force (impulse and peaks) parameters of 7 national-level front crawl swimmers (17.14 ± 2.73 years of swimming; 57.67 ± 1.62 seconds in the 100-m freestyle). The additional resistance was provided by a specially designed parachute. Parachute swimming (PA) and free-swimming (F) conditions were compared at 5 velocities per condition. Video footage was used to calculate the stroke and coordination parameters, and sensors allowed the determination of force parameters. The results showed that (a) an increase in velocity (V) led to increases in SR, IdC, propulsive phase duration, and peak propulsive force (p < 0.05), but no significant change in force impulse per cycle, whatever the condition (PA or F); and (b) in PA conditions, significant increases in the IdC, propulsive phase duration, and force impulse and a decrease in SR were recorded at high velocities (p < 0.05). These results indicated that, in the F condition, swimmers adapted to the change in velocity by modifying stroke and coordination rather than force parameters, whereas the PA condition enhanced the continuity of propulsive action and force development. Added resistance, that is, "parachute training," can be used for specific strength training purposes as long as swimming is performed near maximum velocity.     

The decline of swimming performance with advancing age: a cross-sectional study

The aim of this cross-sectional study was to measure the swimming parameters-speed (V), stroke frequency (SF), and stroke length (SL)- in 162 male athletes aged 50-90 (divided into 7 age groups, from A to G) participating in the World Master Championships in the 200-m freestyle event, and to analyze the rates and magnitudes of their age-associated declines. The swimmers were video-recorded by 2 digital cameras during the competitions and the swimming parameters related to every 50-m section (lap) and to the entire race (average) subsequently measured or calculated. Lap V and SF decreased in the second and third quarter (11 and 4% on average) and increased (3% on average) in the fourth quarter of the race, whereas lap SL decreased from the first to the last 50-m section. Average V (m.s(-1)) decreased from 1.39 +/- 0.09 (group A) to 0.84 +/- 0.11 (group G); average SL (m) decreased from 2.10 +/- 0.20 (group A) to 1.78 +/- 0.19 (group G); and average SF (cycles.s(-1)) decreased from 0.67 +/- 0.06 (group A) to 0.47 +/- 0.04 (group G). One-way analysis of variance showed significant declines in average V, SL, and SF (p < 0.01) across the 7 groups. The swimming parameters were normalized to the highest values (set equal to 100); thereafter, a linear regression curve was fitted and the regression equations calculated. Decline of SF was about 2.5 times steeper than that of SL. It was highlighted that (a) among the swimming parameters, SL is less affected by the ageing process; (b) SL decreased from group A through group C and thereafter tended to keep steady, whereas the trend for SF was opposite. The results have the potential to give master swimmers and their coaches useful information for training program design.     

The effects of ten weeks of resistance and combined plyometric/sprint training with the Meridian Elyte athletic shoe on muscular performance in women

The purpose of this investigation was to examine the combined effects of resistance and sprint/plyometric training with or without the Meridian Elyte athletic shoe on muscular performance in women. Fourteen resistance-trained women were randomly assigned to one of 2 training groups: (a) an athletic shoe (N = 6) (AS) group or (b) the Meridian Elyte (N = 8) (MS) group. Training was performed for 10 weeks and consisted of resistance training for 2 days per week and 2 days per week of sprint/plyometric training. Linear periodized resistance training consisted of 5 exercises per workout (4 lower body, 1 upper body) for 3 sets of 3-12 repetition maximum (RM). Sprint/plyometric training consisted of 5-7 exercises per workout (4-5 plyometric exercises, 40-yd and 60-yd sprints) for 3-6 sets with gradually increasing volume (8 weeks) followed by a 2-week taper phase. Assessments for 1RM squat and bench press, vertical jump, broad jump, sprint speed, and body composition were performed before and following the 10-week training period. Significant increases were observed in both AS and MS groups in 1RM squat (12.0 vs. 14.6 kg), bench press (6.8 vs. 7.4 kg), vertical jump height (3.3 vs. 2.3 cm), and broad jump (17.8 vs. 15.2 cm). Similar decreases in peak 20-, 40-, and 60-m sprint times were observed in both groups (20 m: 0.14 vs. 0.11 seconds; 40 m: 0.29 vs. 0.34 seconds; 60 m: 0.45 vs. 0.46 seconds in AS and MS groups, respectively). However, when sprint endurance (the difference between the fastest and slowest sprint trials) was analyzed, there was a significantly greater improvement at 60 m in the MS group. These results indicated that similar improvements in peak sprint speed and jumping ability were observed following 10 weeks of training with either shoe. However, high-intensity sprint endurance at 60 m increased to a greater extent during training with the Meridian Elyte athletic shoe.     

Effect of propelling surface size on the mechanics and energetics of front crawl swimming

In swimming the propulsive force is generated by giving a velocity change to masses of water. In this process energy is transferred from the swimmer to the water, which cannot be used to propel the swimmer. Theoretical considerations indicated that an increase of the propelling surface size should lead to a reduced loss of energy to the water. Thus, in this study, the effect of artificially enlarging the propelling surface of the hand was examined. The effect was examined in terms of the propelling efficiency during front crawl swimming using the arms alone. The legs were floated with a small buoy as previously described (Toussaint et al., J. appl. Physiol. 65, 2506-2512, 1988a). In ten competitive swimmers (six male, four female) the rate of energy expenditure (power input, Pi), power output (Po), work per stroke cycle (As), distance per stroke cycle (d), work per unit distance (Ad), and propelling efficiency (ep) were determined at various swimming speeds once with and once swimming without paddles. At the same average velocity the effect of swimming with paddles was to reduce Pi, Po, and Ad by 6, 7.6, and 7.5% respectively, but to increase ep and As by 7.8 and 7%. The increase in distance per stroke cycle and the decrease in stroke cycle frequency matched the predicted values based on the theoretical considerations in which the actual increase in propelling surface size was taken into account.     

Benefits of caffeine ingestion on sprint performance in trained and untrained swimmers

The influence of specific training on benefits from caffeine (Caf) ingestion was examined during a sprint test in a group of highly trained swimmers (T) and compared with the response of a group of untrained occasional swimmers (UT). Seven T and seven UT subjects swam freestyle two randomly assigned 2 x 100 m distances, at maximal speed and separated by 20 min of passive recovery, once after Caf (250 mg) and once after placebo (Pla) ingestion. Anaerobic capacity was assessed by the mean velocity (meters per second) during each 100 m and blood was sampled from the fingertip just before and 1, 3, 5, 7, and 9 min after each 100 m for resting and maximal blood lactate concentration ([la-]b,max) determination. The [la-]bmax was significantly enhanced by Caf in both T and UT subjects (P less than 0.01). However, only T subjects exhibited significant improvement in their swimming velocity (P less than 0.01) after Caf or any significant impairment during the second 100 m. In light of these results, it appears that specific training is necessary to benefit from the metabolic adaptations induced by Caf during supramaximal exercise requiring a high anaerobic capacity.     

The Effects of a 6-Week Strength Training on Critical Velocity,Anaerobic Running Distance, 30-M Sprint and Yo-Yo Intermittent Running Test Performances in Male Soccer Players

The objectives of this study were to examine the effects of a moderate intensity strength training on changes in critical velocity (CV), anaerobic running distance (D''), sprint performance and Yo-Yo intermittent running test (Yo-Yo IR1) performances. Methods: two recreational soccer teams were divided in a soccer training only group (SO; n = 13) and a strength and soccer training group (ST; n = 13). Both groups were tested for values of CV, D'', Yo-Yo IR1 distance and 30-m sprint time on two separate occasions (pre and post intervention). The ST group performed a concurrent 6-week upper and lower body strength and soccer training, whilst the SO group performed a soccer only training. Results: after the re-test of all variables, the ST demonstrated significant improvements for both, YoYo IR1 distance (p = 0.002) and CV values (p<0.001) with no significant changes in the SO group. 30-m sprint performance were slightly improved in the ST group with significantly decreased performance times identified in the SO group (p<0.001). Values for D'' were slightly reduced in both groups (ST -44.5 m, 95% CI = -90.6 to 1.6; SO -42.6 m, 95% CI = -88.7 to 3.5). Conclusions: combining a 6-week moderate strength training with soccer training significantly improves CV, Yo-Yo IR1 whilst moderately improving 30-m sprint performances in non-previously resistance trained male soccer players. Critical Velocity can be recommended to coaches as an additional valid testing tool in soccer.     

KINEMATIC VARIABLES AND BLOOD ACID-BASE STATUS IN THE ANALYSIS OF COLLEGIATE SWIMMERS’ ANAEROBIC CAPACITY

Short duration repeated maximal efforts are often used in swimming training to improve lactate tolerance, which gives swimmers the ability to maintain a high work rate for a longer period of time. The aim of the study was to examine the kinematics of swimming and its relation to the changes in blood acid-base status and potassium level. Seven collegiate swimmers, with at least 6 years of training experience, volunteered to participate in the study. The test consisted of 8 x 25 m front crawl performed with maximum effort. The rest period between repetitions was set to five seconds. Blood samples were taken from the fingertip at rest, after warm-up and in the 3rd minute after completion of the test. The swimming was recorded with a video recorder, for later analysis of time, velocity and technique (stroke index). Based on the swimming velocity results, the obtained curve can be divided into rapid decrease of velocity and relatively stable velocities. The breaking point of repetition in swimming velocity was assumed as the swimming velocity threshold and it was highly correlated with the decrease of the blood acid-base status (pH r=0.82, BE r=0.87, HCO₃ ^- r=0.76; p<0.05 in all cases). There was no correlation between stroke index or fatigue index and blood acid-base status. Analysis of the swimming speed in the 8 x 25 m test seems to be helpful in evaluation of lactate tolerance (anaerobic capacity) in collegiate swimmers.     

Swimming performance is reduced by reflective markers intended for the analysis of swimming kinematics

The present study aimed to clarify whether swimming performance is affected by reflective markers being attached to the swimmer’s body, as is required for a kinematic analysis of swimming. Fourteen well-trained male swimmers (21.1 ± 1.7 yrs) performed maximal 50 m front crawl swimming with (W) and without (WO) 25 reflective markers attached to their skin and swimwear. This number represents the minimum required to estimate the body’s center of mass. Fifty meter swimming time, mid-pool swimming velocity, stroke rate, and stroke length were determined using video analysis. We found swimming time to be 3.9 ± 1.6% longer for W condition. Swimming velocity (3.3 ± 1.8%), stroke rate (1.2 ± 2.0%), and stroke length (2.1 ± 2.7%) were also significantly lower for W condition. To elucidate whether the observed reduction in performance was potentially owing to an additional drag force induced by the reflective markers, measured swimming velocity under W condition was compared to a predicted velocity that was calculated based on swimming velocity obtained under WO condition and an estimate of the additional drag force induced by the reflective markers. The mean prediction error and ICC (2,1) for this analysis of measured and predicted velocities was 0.014 m s⁻¹ and 0.894, respectively. Reducing the drag force term led to a decrease in the degree of agreement between the velocities. Together, these results suggest that the reduction in swimming performance resulted, at least in part, from an additional drag force produced by the reflective markers.     

The effects of different speed training protocols on sprint acceleration kinematics and muscle strength and power in field sport athletes

A variety of resistance training interventions are used to improve field sport acceleration (e.g., free sprinting, weights, plyometrics, resisted sprinting). The effects these protocols have on acceleration performance and components of sprint technique have not been clearly defined in the literature. This study assessed 4 common protocols (free sprint training [FST], weight training [WT], plyometric training [PT], and resisted sprint training [RST]) for changes in acceleration kinematics, power, and strength in field sport athletes. Thirty-five men were divided into 4 groups (FST: n = 9; WT: n = 8; PT: n = 9; RST: n = 9) matched for 10-m velocity. Training involved two 60-minute sessions per week for 6 weeks. After the interventions, paired-sample t-tests identified significant (p ≤ 0.05) within-group changes. All the groups increased the 0- to 5-m and 0- to 10-m velocity by 9-10%. The WT and PT groups increased the 5- to 10-m velocity by approximately 10%. All the groups increased step length for all distance intervals. The FST group decreased 0- to 5-m flight time and step frequency in all intervals and increased 0- to 5-m and 0- to 10-m contact time. Power and strength adaptations were protocol specific. The FST group improved horizontal power as measured by a 5-bound test. The FST, PT, and RST groups all improved reactive strength index derived from a 40-cm drop jump, indicating enhanced muscle stretch-shortening capacity during rebound from impacts. The WT group increased absolute and relative strength measured by a 3-repetition maximum squat by approximately 15%. Step length was the major limiting sprint performance factor for the athletes in this study. Correctly administered, each training protocol can be effective in improving acceleration. To increase step length and improve acceleration, field sport athletes should develop specific horizontal and reactive power.     

The effect of assisted and resisted sprint training on acceleration and velocity in Division IA female soccer athletes

This investigation evaluated the effects of a 4-week, 12-session training program using resisted sprint training (RST), assisted sprint training (AST), and traditional sprint training (TST) on maximal velocity and acceleration in National Collegiate Athletic Association (NCAA) Division IA female soccer athletes (n = 27). The subjects, using their respective training modality, completed 10 maximal effort sprints of 20 yd (18.3 m) followed by a 20-yd (18.3 m) deceleration to jog. Repeated measures multivariate analyses of variance and analyses of variance demonstrated significant (p < 0.001) 3-way interactions (time × distance × group) and 2-way interactions (time × group), respectively, for both velocity and acceleration. Paired t-tests demonstrated that maximum 40-yd (36.6-m) velocity increased significantly in both the AST (p < 0.001) and RST (p < 0.05) groups, with no change in the TST group. Five-yard (4.6-m), 15-yd (13.7 m), 5- to 15-yd (4.6- to 13.7-m) acceleration increased significantly (p < 0.01) in the AST group and did not change in the RST and TST groups. Fifteen- to 25-yd (13.7- to 22.9-m) acceleration increased significantly (p < 0.01) in the RST group, decreased significantly (p < 0.01) in the AST group, and was unchanged in the TST group. Twenty-five to 40-yd (22.9- to 36.6-m) acceleration increased significantly (p < 0.05) in the RST group and remained unchanged in the AST and TST groups. It is purposed that the increased 5-yd (4.6-m) and 15-yd (13.7-m) accelerations were the result of enhanced neuromuscular facilitation in response to the 12-session supramaximal training protocol. Accordingly, it is suggested that athletes participating in short distance acceleration events (i.e., ≤15 yd; ≤13.7 m) use AST protocols, whereas athletes participating in events that require greater maximum velocity (i.e., >15 yd; > 13.7 m) should use resisted sprint training protocols.     

Effects of three tapering techniques on the performance, forces and psychometric measures of competitive swimmers

The 100-m and 400-m swim time, tethered swimming forces, mood states and self-ratings of well-being of 27 competitive swimmers were measured before and after 4 weeks of intense training and after 1 week and 2 weeks of tapering for major competition. The swimmers were divided into three groups. Each group completed one of three taper regimes similar to those currently performed by swimmers in preparation for competition: (a) reduced training frequency according to each athlete's daily ratings of well-being, (b) reduced training volume, and (c) reduced training volume and intensity. Significant improvements in the Profile of Mood States measures of tension, depression and anger (P < 0.05) were observed after 1 week of tapering, with significant improvements in total mood disturbance and fatigue (P < 0.05) and peak tethered swimming force (P < 0.01) after 2 weeks. Non-significant improvements in 100-m and 400-m swim time (P > 0.05) were observed and no significant differences were revealed among the three tapering techniques. These data highlighted the importance of providing sufficient recovery before competition, since 1 week of reduced training was not long enough to maximise the benefits of tapering. However, none of the three types of tapering currently used by competitive swimmers could be shown to be more beneficial than the others. Accepted: 9 February 1998     

Estimation of hand forces and propelling efficiency during front crawl swimming with hand paddles

The aim of the study was to investigate possible modifications caused by hand paddles in the relative contribution of the lift and drag forces of the hand and in the propelling efficiency, during front crawl swimming. Eight female swimmers swam 25 m with maximal intensity without paddles, with small (116 cm(2)) and with large paddles (268 cm(2)). Four cameras operating at 60 Hz were used to record the images and the Ariel Performance Analysis System was used for the digitisation. The results showed that, although during swimming with hand paddles the hand's velocity decreased, the greater propulsive area of the hand paddle caused an increase in the drag, lift, resultant and effective forces of the hand. However, the relative contribution of lift and drag forces on swimming propulsion was not modified, nor was the direction of the resultant force. Hand paddles also increased the propelling efficiency, the stroke length and the swimming velocity, mainly because of the larger propulsive areas of the hand in comparison with free swimming. However, the significant decrease of the stroke rate, might argue the effectiveness of hand paddle training, particularly when large paddles are used in front crawl swimming.     

Effect of leg kick on active drag in front-crawl swimming: Comparison of whole stroke and arms-only stroke during front-crawl and the streamlined position

The purpose of this study was to examine the effect of leg kick on the resistance force in front-crawl swimming. The active drag in front-crawl swimming with and without leg motion was evaluated using measured values of residual thrust (MRT method) and compared with the passive drag of the streamlined position (SP) for the same swimmers. Seven male competitive swimmers participated in this study, and the testing was conducted in a swimming flume. Each swimmer performed front-crawl under two conditions: using arms and legs (whole stroke: WS) and using arms only (arms-only stroke: AS). Active drag and passive drag were measured at swimming velocities of 1.1 and 1.3 m s⁻¹ using load cells connected to the swimmer via wires. We calculated a drag coefficient to compare the resistances of the WS, AS and SP at each velocity. For both the WS and AS at both swimming velocities, active drag coefficient was found to be about 1.6–1.9 times larger than that in passive conditions. In contrast, although leg movement did not cause a difference in drag coefficient for front-crawl swimming, there was a large effect size (d = 1.43) at 1.3 m s⁻¹. Therefore, although upper and lower limb movements increase resistance compared to the passive condition, the effect of leg kick on drag may depend on swimming velocity.