The effects of different stretching and warm-up exercise protocols on 50-meter swimming performance in sub-elite women swimmers

Abstract

BACKGROUND:

Warm up exercises are common practice before training and competition in almost every sport. Although, swimming is a popular sport throughout the world, studies on the effects of warm-up are scarce.

OBJECTIVE:

The purpose of this study is to compare the effects of different stretching warm-up and exercise protocols on swim performance.

METHODS:

Fourteen sub-elite college women swimmers volunteered to participate in the study. The four stretching and warm-up protocols they followed were; (I) without stretching (WS); (II) static stretch (SS); (III) in-water (IW); and (IV) dry land (DL).

RESULTS:

There was a significant main effect for 50-meter front crawl (F $=$ 70,453; $p=$ 0.00) and breaststroke swimming performances (F $=$ 145.504; $p=$ 0.000). The best 50-meter front crawl and breaststroke performance detected immediately after IW was 28.1 and next, 39.9 seconds. Pairwise comparison indicated that the best 50-meter front crawl performance monitored after IW protocol was 28.0 $\pm$ 2.9 ( $p=$ 0.000) compared with that after WS – 29.8 $\pm$ 2.3 ( $p=$ 0.000) and after SS – 30.7 $\pm$ 2.2 ( $p=$ 0.000).

CONCLUSIONS:

Pre-event low-intensity IW warm-ups may be optimal for 50-meter front crawl and breaststroke swimming performance.

Keywords

Swimming stretching warm up women front crawl breast stroke

1. Introduction

Pre-training or competition ready stretching exercise protocols (SEPs) and warm-up protocols (WUPs) have attracted the interest of trainers because research indicates that they are associated with some positive effects on performance in sport [1, 2]. In the literature, SEPs and WUPs are classified as different approaches or protocols. Generally, it is suggested that static SEPs (SS), dynamic stretches (DS), ballistic and specific swimming WUPs are carried out on dry-land (DL) and in-water (IW) before training or a competition. During the warm-up, the circulatory system delivers the needed blood to the tissues and the rise in body temperature keeps the body heat constant. Regular workouts increase the minute volume of the heart and there is little increase in the heart rate. Thus, exercise movements that have a positive effect on the circulatory system and development of the vessels contribute to the pumping of the blood from the heart to all parts of the body more easily [3]. WUPs are recommended due to the increment in muscle temperature brought about by the priming exercises as indicated in multiple physiological and metabolic alterations that influence performance in sport [4]. The higher muscle temperature facilitates performance; therefore, it is suggested that temperature may enhance performance by inducing decreases in the viscous resistance of muscle, a speeding up of the rate-limiting oxidative reactions, or an increase in oxygen delivery to muscles [5, 6]. Increased performance is related to vasodilation of muscle blood vessels and a rightward shift of the oxyhaemoglobin-dissociation curve after warm-up. Haemoglobin releases nearly twice as much oxygen at 41 ${}^{\circ}$ C as it does at 36 ${}^{\circ}$ C, and the oxygen dissociates twice as rapidly. A similar effect is demonstrated in the dissociation curve of myoglobin [5, 7]. Moreover, improved temperature is the reason for vasodilation, which improves muscle blood flow. Febbraio et al. [8] have reported that a rise in muscle temperature enhanced muscle glycogenolysis, glycolysis, and high-energy phosphate degradation during exercise. Also, improved muscle temperature could contribute to enhanced performance by increasing the function of the nervous system. Besides, improved muscle temperature increases the transmission speed of nerve impulses and increases the central nervous system function (CNS). Enhanced CNS function may be critical for activities that require rapid reactions and complex body movements [9].

WUPs are a thoroughly acknowledged practice preceding nearly every athletic competition. However, while a warm-up is considered necessary for ideal performance by many trainers and athletes, there is little scientific evidence to support its effectiveness. Additionally, the limited studies conducted have produced conflicting findings. WUPs are generally based on the trial and error experience of the athlete or trainer, rather than on scientific research [4, 5]. Even though WUPs are an extensive practice among swimmers [10], little is known about the optimum procedures that produce improved readiness for a given event. Several factors and the confusion between their relationship mean that any characterisation of the primary properties of the best WUPs is bold. This could be the why the literature reveals complicated findings and the issue has remained separate for some time [4, 1, 11]. There has been some research into the effects of different WUPs on 50 and 100-meter swimming performance [12, 13, 14]. Some studies include the front crawl and others include breast stroke swimming performance [12, 13]. Balilionis et al. [12] found that individual data indicated that 19% of participants performed best in the 50-yd category after short warm-ups (WU), 37 % after no WUs, and 44% after regular WUs. The heart rate was significantly higher after regular WUs (100 $\pm$ 13 bpm) when compared with the no WUs category (88 $\pm$ 18 bpm). However, no significant differences among WUs were found for reaction time ( $p=$ 0.96), rating of perceived exertion post 50-yd time trial ( $p=$ 0.11), dive distance ( $p=$ 0.67), or stroke count ( $p=$ 0.23). Neiva et al. [13] found that performance in the 100-meter was fastest in the warm-up condition (67.15 $\pm$ 5.60 vs 68.10 $\pm$ 5.14 seconds; $p=$ 0.01), although three swimmers swam faster without any warm-ups. Critical to this was the first 50-meter lap (32.10 $\pm$ 2.59 vs 32.78 $\pm$ 2.33 seconds; $p<$ 0.01), where the swimmers presented a higher distance per stroke (2.06 $\pm$ 0.19 vs. 1.98 $\pm$ 0.16 m; $p=$ 0.04) and swimming efficiency compared with the no-warm-up condition (stroke index 3.46 $\pm$ 0.53 vs 3.14 $\pm$ 0.44 m ${}^{2}\cdot$ c ${}^{-1}\cdot$ s ${}^{-1}$ ; $p<$ 0 .01). Neiva et al. [13] suggests that pre-events in water WUs significantly improves performance. Specifically, in our study it was found that in water warm-ups improved the 50-meter front crawl (28 seconds) and breaststroke (39.7 seconds) swimming performance. This finding was consistent with the aforementioned literature samples.

Figure 1.

Experimental design flowchart.

However, there is no one study that specifically mentions the effects of different SEPs and WUPs on both the 50-meter front crawl and breaststroke swimming performance.

The purpose of this study was thus to examine different SEPs and WUPs on swimming performance on sub-elite women swimmers. We hypothesized that IW warm-up would positively contribute to the swimmers’ response in maximal 50-meter front crawl and breaststroke swimming performance. It was also hypothesised that SS would negatively affect swimmers’ response to 50 meter front crawl.

2. Methods

2.1 Subjects

Fourteen sub-elite i.e. individuals who had not achieved the elites’ criteria, yet all qualified for at least one Turkey National Championship, college women swimmers volunteered to participate in the study. Their age, height, body mass, body fat and body mass index were 22.5 $\pm$ 2.5 years; 163 $\pm$ 4.1 cm; 56.8 $\pm$ 2.3 kg, 20.4 $\pm$ 1.2% and 21.3 $\pm$ 3.2 kg/m ${}^{2}$ , respectively. All swimmers had five years’ experience in training and competition and practiced the specific sport for at least 16 h/wk. To be included in the study, the swimmers had to have the following characteristics: (a) been sub-elite with at least five years’ experience in the sport; (b) without any functional limitations that could interfere in the test performance; (c) no medical condition that could influence the tests; (d) maintained regular physical activity during the course of the study. All swimmers read and signed a consent form. The study was approved by the Research Ethics Committee of Inonu University. All swimmers were required to keep to the same training, recovery, and diet habits during the evaluation days. They had to avoid vigorous exercise, refrain from smoking and consuming caffeine and ergogenic aids for 48 hours before testing days. Before all swimming tests the volunteers were asked about their night sleep status and tests were only carried out on those who had slept for at least seven to eight hours. Any swimmers who expressed sleeping problems were removed from the swim test.

2.2 Procedure

There is only one group of swimmers in the study. They participated in two familiarisation and eight data collection sessions in an indoor swimming pool. Prior to data collection, all swimmers participated in two familiarisation sessions during which they practiced all SEPs and WUPs. This introductory period was designed to reduce the influence of any learning effects caused solely by the mechanics of performing the study protocols. Each stretching and warm-up protocol lasted between 10 and 12 minutes. Swimmers warmed up in groups, and two coaches supervised each period of SEPs and WUPs. All swimmers were asked not to participate in any moderate to vigorous physical activity before each SEP and WUP session. Throughout the familiarisation sessions the swimmers became familiar with the different SEPs and WUPs (WS, SS, IW, and DL). The entire SEPs and WUPs were carried out at the same time of day (10.00 am, to avoid the effect of diurnal variations) in a swimming pool with a water temperature of 27 ${}^{\circ}$ C–28.5 ${}^{\circ}$ C, air temperature of 25 ${}^{\circ}$ C–27.5 ${}^{\circ}$ C, and 56–59% of humidity (using the Kestrel 4500 Pocket Weather Tracker, Nielsen-Kellerman Co., USA). Each swimmer was assigned to one warm-up procedure, and the use of competition swimsuits was allowed. The trials were performed individually to prevent pacing or tactics effects. After reaching the pool, the swimmers were seated for five minutes, with their legs uncrossed, to assess the baseline measurement of heart rates. Then they performed one of the protocols (WS, SS, IW, and DL, respectively), immediately followed by 50-meter swimming performance tests. The rest period between each series was three minutes. When the heart rate of the subjects reached the range of 110–120 bpm, the performance measurement began. After that, all swimmers were given an interval of almost ten minutes passive rest. All ten sessions were completed during the course of almost 30 days, so that between 48 and 72 hours separated each testing day (two or three times per week); this was done to minimise any performance changes that could occur over a longer time period.

2.3 SEPs and WUPs Sessions

During the SEPs and WUPs sessions, the participants stretched the main muscle groups they would use during the front crawl and breaststroke (shoulders, biceps, triceps, back, abdominal, quadriceps and hamstring muscles). The repetitions of 50-meter tests started just as they would in any official competition with front crawl swimming. The heart rate was recorded every five seconds. After each protocol, the monitors were interfaced with a computer and the heart rate data was downloaded for statistical analysis. The swimmers wore portable heart rate monitors (Polar V800 Electro Inc, Kempele, Finland) during each of the WUPs. Monitors were attached to the swimmers with a lightweight chest strap and wristwatch. A secondary analysis was performed to assess the cardiorespiratory demand.

WS: All swimmers did five minutes run, then were seated for three minutes and did not perform any stretching.

SS: After the five minutes run each participant stretched the target muscles of the right upper and lower extremities slowly and carefully until they reached a position where they felt mild discomfort for 30 seconds. Immediately after this, stretching was implemented in the same manner on a similar target muscle on the left side. This sequence was applied twice. The next target upper or lower extremities muscle was stretched after a rest period of ten seconds in accordance with the guidelines from the American College of Sport Medicine [15]. The SEPs were implemented using the horizontal flexors and extensors of muscles (see Table 1).

Table 1
Static stretching exercises

1	Horizontal extensor shoulder stretch: While sitting raise arm and pull elbow across chest to bring scapula further from spine.
2	Horizontal flexor shoulder stretch: Stand with right side facing a wall, place hand on the wall at shoulder height with elbow straight and thumb pointing down, turn body away from the wall and maintain the rotation of arm.
3	Pectoral stretch: Position elbows below your shoulder level. With forearms at a 90-degree angle to arms, place hands firmly against the outside of the doorframe. Step forward with right leg, keeping arms firmly on the door. Should feel a pull in your pectorals muscle between shoulders and chest.
4	Latissimus dorsi Stretch: Stand with feet shoulder width apart, chest up and head back over the shoulders, raise the right arm overhead and grab right elbow with the left hand, pull right elbow over to the left gently and bend trunk to the left until a comfortable stretch is felt.
5	Adductor stretch: In the seated position with an erect spine, touch soles of feet together, bend knees, and allow knees to drop.
6	Modified hurdlers stretch: In a seated position with one leg straight, place the other leg on the inside of the straight leg and reach forward.
7	Hip rotator stretch: In a supine position, cross one leg over the other, and flex both hips to or by pulling on the uncrossed leg.
8	Bent-over toe raise: From a standing position with the heel of one foot slightly in front of the toes of the other foot, dorsi flex front foot towards shin while leaning downward with upper body.
9	Quadriceps stretch: In the standing position with an erect spine, bend one knee and bring heel towards buttocks while holding the foot with one hand.
10	Calf stretch: In a standing position with feet staggered about 2 or 3 feet from a wall, lean against the wall with both hands, keeping the back leg straight and the front leg slightly bent.

Table 2

Dry-land warm-up exercises

1	High-knee walk: While walking, lift knee towards chest, raise body on toes, and swing alternating arms.
2	Straight-leg march: While walking with both arms extended in front of body, lift one extended leg towards hands then return to starting position before repeating with other leg.
3	Hand walk: With hands and feet on the ground and limbs extended, walk feet towards hands while keeping legs extended then walk hands forward while keeping limbs extended.
4	Lunge walks: Lunge forward with alternating legs while keeping torso vertical.
5	Backward lunge: Move backwards by reaching each leg as far back as possible.
6	High-knee skip: While skipping, emphasize height, high knee lift, and arm action.
7	Lateral shuffle: Move laterally quickly without crossing feet.
8	Back pedal: While keeping feet under hips, take small steps to move backwards rapidly.
9	Heel-ups: Rapidly kick heels towards buttocks while moving forward.
10	High-knee run: Emphasize knee lift and arm swing while moving forward quickly.

IW: The warming heart rate of swimmers were determined as 40% of the maximal heart rate. The maximum 50-meter swimming performance were determined according to heart rate of the swimmer using the Karvonen formula [12, 16]. The first 50-meter front crawl swimming test in each condition started ten minutes after a warm-up of 1200-meters that included a 400-meter moderate swim, four x 50-meter leg kicks, four x 50-meter swimming drills, four x 50-meter swims that progressively increased in speed, a 25-meter sprint, and 100 to 150-meters of easy swimming [17].

DL: This warm-up protocol consisted of 10 minutes of 10 DL exercises that increased in intensity from moderate to high (see Table 2). The swimmers performed each DL exercise over a 13-meter distance, then rested for approximately 10 seconds, then repeated a similar exercise for 13-meter after which they returned to the starting point. All swimmers were continually instructed to maintain proper form throughout the performance of the DL protocol (e.g. vertical torso, knees towards chest, up on their toes etc.). This protocol was created so as to be in keeping with the WUPs typically used to prepare athletes for sports participation [18, 19].

2.4 Rating of perceived exertion (RPE)

The volunteers were asked to rate the WUPs and 50-meter front crawl and breaststroke swim performance using Borg’s 15-point scale [20]. The scale was clarified in detail and assisted by a visual aid. The RPE was defined post-all WUPs and post 50-meter front crawl and after each breaststroke swim performance [12].

2.5 Swim performance

In each trial, the swimmer was requested to set on the starting block and to take off after official verbal commands and the starting signal. The swimmers began the time trials with a dive from the starting blocks. All swim performances were manually recorded (using Adidas GR 10 Coach stopwatch, Germany) by an experienced coach (holding a Turkish State-National level licence). The footage from digital video cameras (Canon HD HF 10, Tokyo, Japan) positioned at the 5, 25 and 45-meter marks was used to determine the start [21].

2.6 Statistical analysis

The statistical analysis was initially carried out using the ‘Shapiro Wilks’ normality test and the homoscedasticity test. All the variables presented normal distribution and homoscedasticity. The effects of the four SEPs and WUPs protocols were analysed using an ‘ANOVA for Repeated Measures’ (WS x SS x IW x DL) and the sphericity was checked using ‘Mauchly’s Test’. When the assumption of sphericity was not met, the significance of the F ratios was adjusted according to the ‘Greenhouse-Geisser’ procedure. Pairwise tests were run to further investigate the effect of each condition. The effect sizes were calculated and classified to determine the magnitude of changes among the experimental conditions as proposed by ‘Cohen’s d’. An effect size classified as 0.2 was deemed small, 0.5 medium, and 0.8 large [22]. The findings are presented as mean $\pm$ standard deviation (SD). An alpha level of $p<$ 0.05 was considered statistically significant for all analyses. All data analysis was conducted using SPSS version 22.0 (IBM for OSX).

3. Results

3.1 Swim performance

There was a substantial main effect among WUPs on the 50-meter front crawl (F $=$ 70.453; $p=$ 0.00) and breaststroke (F $=$ 140.132; $p=$ 0.000) swim performance. The best 50-meter front crawl and breaststroke performance detected immediately after IW was 28.11 and next, 39.91 seconds. Pairwise comparison indicated that the best 50-meter front crawl swimming performance monitored after IW protocol was M $=$ 28.0 $\pm$ 2.9, $p=$ 0.000 compared with that after WS (M $=$ 29.8 $\pm$ 2.3, $p=$ 0.000) and after SS (M $=$ 30.7 $\pm$ 2.2, $p=$ 0.000). No significant difference was found between WS and SS protocols for 50-meter front crawl ( $p=$ 0.437) and breaststroke ( $p=$ 0.574) swim performance. Nor was there any significant difference between IW and DL WUPs for the 50-meter front crawl ( $p=$ 0.873) and breaststroke ( $p=$ 0.128) .

3.2 Heart rate

There was no significant main effect between the SEPs and WUPs for the HR 50-meter front crawl ( $p=$ 0.749) and breaststroke ( $p=$ 0.815). A significant main effect among four SEPs and WUPs was found for the HRPre 50-meter front crawl ( $p=$ 0.037) and breaststroke ( $p=$ 0.025). Post-hoc measures ascertained that HRPre was significantly higher ( $p=$ 0.016, $p=$ 0.028 respectively) after IW (105.8 $\pm$ 11 bpm) compared with WS (88.7 $\pm$ 8.4 bpm) and SS (91.4 $\pm$ 9.7 bpm). Also, post-hoc measures found that HRPre was significantly higher ( $p=$ 0.019, $p=$ 0.034 respectively) after IW (109.6 $\pm$ 13 bpm) compared with WS (91.1 $\pm$ 8.3 bpm) and SS (93.7 $\pm$ 10 bpm). No significant difference was found between IW and DL WUPs before both swimming performances ( $p=$ 0.418, $p=$ 0.452 respectively).

There was a significant main effect for the HR post 50-meter front crawl ( $p=$ 0.020) and breaststroke ( $p=$ 0.010) swim performance among four SEPs and WUPs. The heart rate was significantly higher ( $p=$ 0.033, $p=$ 0.018) after the IW 50-meterfront crawl swim performance (178.9 $\pm$ 16 bpm) protocol compared with that after WS (164.0 $\pm$ 12 bpm) and SS (160.7 $\pm$ 15 bpm). No significant differences ( $p=$ 0.676) were revealed between WS (162.0 $\pm$ 12 bpm) and SS (160.7 $\pm$ 15 bpm), IW (178.9 $\pm$ 16 bpm) and DL (172.5 $\pm$ 15 bpm) for 50-meter front crawl ( $p=$ 0.083). In addition, the heart rate was significantly higher ( $p=$ 0.042, $p=$ 0.038) after the IW 50-meter breaststroke protocol (174.9 $\pm$ 17 bpm) compared with that after the WS (163.1 $\pm$ 16 bpm) and SS (162.0 $\pm$ 14 bpm). No significant differences ( $p=$ 0.866) were revealed between the WS (163.1 $\pm$ 16 bpm) and SS (162.0 $\pm$ 14 bpm), IW (174.9 $\pm$ 17 bpm) and DL (171.1 $\pm$ 14 bpm) 50-meter breaststroke swim performance ( $p=$ 0.519).

Table 3
The main effect of WS, SS, IW, and DL, SEPs and WUPs on 50-meter front crawl and breaststroke swim performance, pre and post HR, warm-up RPE, 50-meter swim RPE ( $n=$ 14, values are given as mean $\pm$ standard deviation)

Parameters	WS		SS		IW		DL		$p$
50-meter front crawl (seconds)	29.8	$\pm$ 2.3	30.7	$\pm$ 2.2	28.0	$\pm$ 2.9*	28.4	$\pm$ 3.1†	0.000
HRR (bpm)	61.4	$\pm$ 6.5	60.5	$\pm$ 5.2	59.7	$\pm$ 6.8	61.2	$\pm$ 8.4	0.749
HRPre 50-meter	88.7	$\pm$ 8.4	91.4	$\pm$ 9.7	105.8	$\pm$ 11*	103.9	$\pm$ 12†	0.037
HRPost 50-meter	162.0	$\pm$ 12	160.7	$\pm$ 15	178.9	$\pm$ 16*	172.5	$\pm$ 15†	0.020
SEP and WUP RPE	8.7	$\pm$ 1.1	9.4	$\pm$ 1.4	11.3	$\pm$ 2.7*	11.6	$\pm$ 2.4†	0.041
50-meter swim RPE	15.4	$\pm$ 2.2	15.1	$\pm$ 2.4	15.5	$\pm$ 2.3	15.9	$\pm$ 2.1	0.864
50-meter breaststroke (seconds)	41.5	$\pm$ 2.9	41.8	$\pm$ 2.1	39.7	$\pm$ 2.6*	40.5	$\pm$ 2.7†	0.000
HRR (bpm)	60.2	$\pm$ 9.2	59.7	$\pm$ 8.5	60.4	$\pm$ 5.7	59.9	$\pm$ 7.3	0.815
HRPre 50-meter	91.1	$\pm$ 8.3	93.7	$\pm$ 10	109.6	$\pm$ 13*	107.1	$\pm$ 12†	0.025
HRPost 50-meter	163.1	$\pm$ 16	162.0	$\pm$ 14	174.9	$\pm$ 17*	171.1	$\pm$ 14†	0.010
SEP and WUP RPE	8.9	$\pm$ 1.3	9.9	$\pm$ 1.8	11.7	$\pm$ 2.3*	11.2	$\pm$ 2.9†	0.028
50 meter swim RPE	15.6	$\pm$ 1.9	15.1	$\pm$ 2.0	15.5	$\pm$ 1.7	15.9	$\pm$ 1.8	0.864

(WS: Without Stretch, SS: Static Stretch, IW: In-water, DL: Dry-land, HRR: Heart rate resting; HRPre: Heart rate pre swim time; HRPost: Heart rate post swim time; WUP RPE: Rating of perceived exertion; Warm-up protocol bpm: beat per minute; *: Significant difference ( $p<$ 0.05) between IW and WS, SS; †: Significant difference ( $p<$ 0.05) between DL and WS, SS.)

Table 4

Effect size values

50-meter front crawl swim			50-meter breaststroke swim
WUPs	ES	Magnitude	WUPs	ES	Magnitude
WS vs SS	0.47	Small	WS vs SS	0.28	Small
WS vs IW	0.50	Moderate	WS vs IW	0.64	Moderate
WS vs DL	0.25	Small	WS vs DL	0.28	Small
SS vs IW	0.94	Large	SS vs IW	0.47	Moderate
SS vs DL	0.75	Moderate	SS vs DL	0.20	Small
IW vs DL	0.28	Small	IW vs DL	0.24	Small

WS: without stretching; SS: static stretch; IW: in-water; DL: dry-land; ES: effect size.

3.3 Ratings of perceived exertion (RPE)

The RPEs for each trial are shown in Table 3. A significant main effect for the RPEs after WUPs were explored with the following results; front crawl, $p=$ 0.027 and breaststroke, $p=$ 0.030. The RPE was significantly higher ( $p=$ 0.016, $p=$ 0.029 respectively) after IW (11.3 $\pm$ 2.7 point) compared with that after WS (8.7 $\pm$ 1.1 point) and SS (9.4 $\pm$ 1.4 point) before the front crawl. In addition, the RPE was significantly higher ( $p=$ 0.021, $p=$ 0.037 respectively) after IW (11.7 $\pm$ 2.3 point) compared with that after WS (8.9 $\pm$ 1.3 point) and SS (9.9 $\pm$ 1.8 point) before the breaststroke. No significant differences were revealed between the WS and SS, IW and DL for both 50-meter swim performances ( $p>$ 0.05).

Table 4 shows a comparison between the 50-meter front crawl and breaststroke and the values of effect size in terms of four WUPs. In the 50-meter IW trial, the swimmers were faster, with small magnitudes of difference (ES $>$ 0.28) resulting from the large ES ( $>$ 0.94) noted in the 50-meter front crawl. Also, the swimmers were faster, with small magnitudes of difference (ES $>$ 0.24) resulting from the large ES ( $>$ 0.68) in the 50-meter breaststroke.

4. Discussion

The purpose of the current study was to compare the effects of different WUPs on maximal 50-meter front crawl and breaststroke swim performance. 50-meter front crawl and breaststroke swimming were selected because measuring any longer swimming protocols would have decreased the effect of the WUPs [21]. Our main results can be summarised as follows: (1) the four WUPs caused a different effect on the 50-meter front crawl and breaststroke swimming performance, (2) the best 50-meter front crawl and breaststroke was found after IW protocol and compared with that after WS, SS, and DL. These results provide evidence for the positive effect that IW protocols can have on front crawl and breaststroke performance and serve to confirm what other previous studies have found [6, 12, 13, 23]. Until now, there have been few investigations into front crawl and breaststroke performance using four WUPs. Previous research has been sceptical about several of the findings and there was some disagreement with the evidence of the effects of WUPs. One study found a significantly faster 100-yard swim time after 15 minutes of swimming WUs compared with no WUs [24] which supports the findings of our study. However, some studies found no significant differences in 50 and 100-meter swim times between 400 or 800-meter swims with WUs and without [25]. A possible explanation for this could be that there is insufficient time to increase muscle and core temperatures and also due to the design of the study. The RPE after front crawl and breaststroke 50-meter swimming was not significantly different among the WUPs. This shows that swimmers produced the same results after each 50-meter swim trial regardless of WUPs and despite the variable levels of RPE beforehand. Our study supports the findings of Balilionis et al. [12] and Romney and Nethery [25], who found that the RPEs were not significantly different between the WUPs after a 100-yard trial.

Swimming WUPs serve to raise the body’s core temperature, improve blood flow, respiration rate, HR, and flexibility of the muscles, which may prepare a swimmer for optimal swimming performance [5, 12]. In our study, HR was significantly different after four WUPs. These findings help to support the earlier results by Mitchell and Huston [24]. Formerly, reported improvements in swimming performance after IW protocols have been connected to an increase in the HR causing an increase in the baseline VO ${}_{2}$ , improved muscle and core temperature [5, 12]. An increase in tissue temperature is an elusive component in all WUPs, and many of the physiological changes, including cardiovascular regulations, may be connected to this phenomenon. Although muscle and core temperature were not measured in the current study, other studies have indicated a relationship between elevated heart rates following various WUPs [4, 6, 18, 24, 27, 28]. Thus, there may be a relationship between the heart rate results in the current research and possible elevations in tissue temperature. Also, in our study, the IW protocol continued for between 10 and 12 minutes. As would be anticipated, the RPE rates show that the IW protocol, rated as ‘somewhat hard’, was perceived as significantly harder compared with the other three WUPs. As a result, increases in 50-meter swim performance after the IW protocol may be attributed to enhanced core and muscle temperatures.

Regarding the main purpose of the current study, the swimmers performed second fastest in the 50-meter front crawl and breaststroke after a DL warm-up. In terms of DL warm-ups, some studies have reported that swimming performance is similar to that produced following an IW warm-up [20, 29, 30]. These results show that a DL warm-up might be a potential alternative for swimmers. Furthermore, one study reported that psychological changes might enhance performance in athletes and indicated that warm-ups improve readiness and ensure there is sufficient time to concentrate before the training and the race. This might contribute to the best performance in the 50-meter front crawl and breaststroke swimming after IW. A reason for this could be that some swimmers are demoralised and lack motivation to race with WS and SS which could explain a tendency towards slower performance in the 50-meter front crawl and breaststroke WS and SS WUPs in this research.

SS practices are widespread in the warm-up routines of athletes and strength practitioners in an attempt to enhance their performance and decrease the risk of injury [31]. But previous studies have indicated that SS acutely reduced maximal strength [32, 33], strength endurance [34], and power [35]. Kokkonen et al. [34] suggested that pre-event static stretching significantly decreased jump height. Specifically, in our study SS warm-up decreased the 50-meter front crawl (30.35 seconds) and breaststroke (41.8 seconds) performance. This finding is consistent with those in the aforementioned studies. Our study suggests that pre-event SS warm-ups may influence neural mechanisms that could adversely affect muscular performance during swimming training or competitions by reducing motor unit activation and muscle-tendon unit stiffness [32, 36, 37]. Also, theoretically, greater muscle activation for a given velocity may increase energy expenditure and therefore, accelerate the onset of fatigue [31].

In summary, carrying out the SS protocols acutely decreased the 50-meter swimming performances. We also provide evidence that pre-event low-intensity IW warm-ups may be optimal for the 50-meter front crawl and breaststroke swimming performance. However, further study is required to investigate the impact of a WU effect on longer swimming event times.

Some limitations of the current research should be mentioned. First, a potential concern in the present research may be the single gender design and the small number of participants.. Second, this research was performed for a specific race event (50-meter); different distances (100, 200-meter, etc.) or swimming techniques (backstroke, butterfly) may elicit different adaptations, as might different ages and use of male swimmers.

5. Conclusions

The IW warm-ups performed by the swimmers were effective in optimising their 50-meter front crawl and breaststroke swimming performance. Some positive responses to DL revealed the swimmers’ individuality and confirmed the idea that warm-up procedures should be considered as an individualised approach to optimising swimmer performance. Thus, there is no single model that should be copied and adopted by all swimmers. It is fundamental to consider the biological individualities of swimmers, and therefore, group procedures should be handled with caution as they risk compromising optimal performances. Swimmers and coaches should carry out tests on more than one occasion to establish consistent responses to different WUPs and thereby establish their own individual and optimal warm-ups. However, the results are clear in demonstrating a positive effect, so future research is required to better understand the ideal structure of warm-up procedures for swimmers.

Footnotes

Conflict of interest

The authors have no conflicts of interest to declare.

References

Fradkin

Zazryn

Smoliga

. Effects of warming-up on physical performance: a systematic review with meta-analysis. J Strength Cond Res. 2010; 24: 140-8.

Neiva

Marques

Barbosa

Izquierdo

Marinho

. Warm-up and performance in competitive swimming. Sports Med. 2014; 44: 319-30.

Akgün

. Egzersiz Fizyolojisi, 3. Baskı, I. Cilt, Ankara, 1989.

Bishop

. Warm-up II: Performance changes following active warm-up and how to structure the warm-up. Sports Med. 2003; 33: 483-98.

Bishop

. Warm-up I: Potential mechanisms and the effects of passive warm-up on exercise performance. Sports Med. 2003; 33: 439-54.

Zochowski

Johnson

Sleivert

. Effects of varying post-warm-up recovery time on 200-m time-trial swim performance. Int J Sport Physiol. 2007; 2: 201-11.

Barcroft

King

. The effect of temperature on the dissociation curve of blood. J Physiol. 1909; 39: 374-84.

Febbraio

Carey

Snow

Stathis

Hargreaves

. Influence of elevated muscle temperature on metabolism during intense exercise. Am J Physiol. 1996; 271: 1251-5.

Ross

Leveritt

. Long-term metabolic and skeletal muscle adaptations to short-sprint training: implications for sprint training and tapering. Sports Med. 2001; 31: 1063-82.

10.

McGowan

Rattray

Thompson

Pyne

Raglin

. Current warm-up practices and the contemporary issues faced by elite swimming coaches. J Strength Cond Res. 2016; 30: 3471-80.

11.

Neiva

Marques

Barbosa

Izquierdo

Viana

Teixeira

Mandarin

. The effects of different warm-up volumes on the 100-m swimming performance: A randomized crossover study. J Strength Cond Res. 2015; 29: 3026-36.

12.

Balilionis

Nepocatych

Ellis

Richardson

Neggers

Bishop

. Effects of different types of warm-up on swimming performance, reaction time, and dive distance. J Strength Cond Res. 2012; 26: 3297-303.

13.

Neiva

Marques

Fernandes

Viana

Barbosa

Marinho

. Does warm-up have a beneficial effect on 100-m freestyle? Int J Sport Physiol. 2014; 9: 145-50.

14.

Neiva

Morouço

Pereira

Marinho

. The effect of warm-up in 50 m swimming performance. J Motricidade. 2012; 8: 13-18.

15.

Walter

Thompson Neil

Gordon Linda

, Pescatello. American College of Sports Medicine. Musculoskeletal exercise prescription. Chapter 29. In: ACSM’s guidelines for exercise testing and prescription. Philadelphia, PA: Wolters Kluwer/Lippincott Williams and Wilkins, 2010.

16.

Karvonen

Kentala

Mustala

. The effects of training on heart rate; a longitudinal study. Ann Med Exp Biol Fenn. 1957; 35: 307-15.

17.

Toubekis

Tsolaki

Smilios

Douda

Kourtesis

Tokmakidis

. Swimming performance after passive and active recovery of various durations. Int J Sport Physiol. 2008; 3: 375-86.

18.

Mann

Jones

. Guidelines to the implementation of a dynamic stretching program. Strength Cond J. 1999; 21: 53-5.

19.

Faigenbaum

Bellucci

Bernieri

Bakker

Hoorens

. Acute effects of different warm-up protocols on fitness performance in children. J Strength Cond Res. 2005; 19: 376-81.

20.

Borg

. Borg’s perceived exertion and pain scales. Champaign, IL: Human Kinetics, 1998.

21.

Kilduff

Cunningham

Owen

West

Bracken

Cook

. Effect of post activation potentiation on swimming starts in international sprint swimmers. J Strength Cond Res. 2011; 25: 2418-23.

22.

Cohen

. Statistical power analysis for the behavioural sciences (2nd edition). Hillsdale, NJ: Lawrence Erlbaum Associates, 1988.

23.

Avela

Finni

Liikavainio

Niemela

Komi

. Neuraland mechanical responses of the triceps surae muscle group after 1 h of repeated fast passive stretches. J Appl Physiol. 2004; 96: 2325-32.

24.

Mitchell

Huston

. The effect of high-and low-intensity warm-up on the physiological responses to a standardized swim and tethered swimming performance. J Sport Sci. 1993; 11: 159-65.

25.

Romney

Nethery

. The effects of swimming and dryland warm-ups on 100-yard freestyle performance in collegiate swimmers. J Swimming Res. 1993; 9: 5-9.

26.

Cavagna

. Effect of temperature and velocity of stretching on stress relaxation of contracting frog muscle fibres. J Physiol. 1993; 462: 161-73.

27.

Ingjer

Stromme

. Effects of active, passive or no warm-up on the physiological response to heavy exercise. Eur J Appl Physiol Occup Physiol. 1979; 40: 273-82.

28.

Arnett

. Effects of prolonged and reduced warm-ups on diurnal variation in body temperature and swim performance. J Strength Cond Res. 2002; 16: 256-61.

29.

Nepocatych

Bishop

Balilionis

Richardson

Hubner

. Acute effect of upper-body vibration on performance in master swimmers. J Strength Cond Res. 2010; 24: 3396-403.

30.

Al-Nawaiseh

Albiero

Bishop

. Impact of different warm-up procedures on a 50-yard swimming sprint. Int. J. Acad. Res. 2013; 5: 44-8.

31.

Lowery

Joy

Brown

De Souza

Wistocki

Davis

Wilson

. Effects of static stretching on 1-mile uphill run performance. J Strength Cond Res. 2014; 28: 161-7.

32.

Fowles

Sale,

MacDougall

. Reduced strength after passive stretch of the human plantar flexors. J Appl Physiol. 2000; 89: 1179-88.

33.

Nelson

Kokkonen

Arnall

. Acute muscle stretching inhibits muscle strength endurance performance. J Strength Cond Res. 2005; 19: 338-43.

34.

Kokkonen

Nelson

Cornwell

. Acute muscle stretching inhibits maximal strength performance. Res Q Exerc Sport, 1998; 69: 411-5.

35.

Behm

Kibele

. Effects of differing intensities of static stretching on jump performance. Eur J Appl Physiol. 2007; 101: 587-94.

36.

Kubo

Kanehisa

Fukunaga

. Effects of resistance and stretching training programmes on the viscoelastic properties of human tendon structures in vivo. J Physiol. 2002; 538: 219-26.

37.

Herda

Cramer

Ryan

McHugh

Stout

. Acute effects of static versus dynamic stretching on isometric peak torque, electromyography, and mechanomyography of the biceps femoris muscle. J Strength Cond Res. 2008; 22: 809-17.

The effects of different stretching and warm-up exercise protocols on 50-meter swimming performance in sub-elite women swimmers

Abstract

BACKGROUND:

OBJECTIVE:

METHODS:

RESULTS:

CONCLUSIONS:

Keywords

1. Introduction

2.1 Subjects

2.2 Procedure

2.3 SEPs and WUPs Sessions

Table 1 Static stretching exercises

2.5 Swim performance

2.6 Statistical analysis

3. Results

3.1 Swim performance

3.2 Heart rate

Table 3 The main effect of WS, SS, IW, and DL, SEPs and WUPs on 50-meter front crawl and breaststroke swim performance, pre and post HR, warm-up RPE, 50-meter swim RPE ( n = 14, values are given as mean ± standard deviation)

4. Discussion

5. Conclusions

Footnotes

Conflict of interest

References

Table 1
Static stretching exercises

Table 3
The main effect of WS, SS, IW, and DL, SEPs and WUPs on 50-meter front crawl and breaststroke swim performance, pre and post HR, warm-up RPE, 50-meter swim RPE ( $n=$ 14, values are given as mean $\pm$ standard deviation)