Hematological and Running Performance Modification of Trained Athletes after Reverse vs. Block Training Periodization

m of the present study was to analyze the e ect of block (BP) and a reverse training periodization (RP) in the hematological and running performance of amateur trained athletes. Modi cations in hematological, aerobic, and anaerobic running performance and countermovement jump before and after twelve weeks of BP vs. RP training programs were analyzed in 16 trained athletes (eight males: 40.0 6.2 years; 179.2 12.8 cm; 73.8 12.2 kg; and eight females: 34.2 4.1 years; 163.4 9.6 cm; 57.0 11.0 kg). A signi cant decrease in heart rate (HR) at ventilatory threshold (VT1) (p=0.031; ES=1.40) was observed in RP without changes in BP. In addition, RP increased signi cantly VO2max (p=0.004; ES=0.47), speed at VO2max (p=0.001; ES=1.07), HR at VT2 (p<0.001; ES=1.32) and VT1 (p=0.046; ES=0.57), while BP improved VO2max (p=0.004; ES=0.51), speed at VO2max (p=0.016; ES=0.92), and HR at VT2 (p=0.023; ES=0.78). In addition, only RP increased anaerobic performance in a running-based anaerobic sprint test (RAST) (mean sprint:p=0.009; ES=0.40, best sprint:p=0.019; ES=0.30 and total time:p=0.009; ES=0.40). Moreover, both types of training periodization proposed in this study maintained hematological values and e ciently improved jump performance (p=0.044; ES=0.6) in RP andp=0.001; ES=0.75 in BP). Therefore, twelve weeks of either RP or BP is an e ective strategy to increase jump and aerobic running performance maintaining hematological values, but only RP increases anaerobic running performance. Keywords:endurance; heart rate; runners; triglycerides; VO2max 1. Introduction Sports performance is a complex combination of psychological and

e ciently improved jump performance (p=0.044; ES=0.6) in RP andp=0.001; ES=0.75 in BP). Therefore, twelve weeks of either RP or BP is an e ective strategy to increase jump and aerobic running performance maintaining hematological values, but only RP increases anaerobic running performance. Keywords:endurance; heart rate; runners; triglycerides; VO2max 1. Introduction Sports performance is a complex combination of psychological and physiological modi cations on the athlete's organism. Speci cally, in endurance athletes, the physiological modi cations related with success have been clearly de ned by previous researchers, in which maximal oxygen uptake (VO2max), lactate threshold, and e ciency appear to play key roles in endurance performance [1]. Along this line, the VO2max and lactate threshold interact to determine the maximal oxygen consumption that could be sustained for a given period of time, being the most used predictors of elite performance. As well as the anaerobic threshold, the ventilatory threshold is one of the physiological parameters related speci cally with endurance and ultra-endurance performance, being a trainable parameter and having a direct e ect on competition performance [2,3]. To reach the physiological adaptations previously mentioned, hematological and chemical modi cation must occur. Di erent modi cations in red blood cells, blood iron, and iron reserve cells as Int. J. Environ. Res. Public Health2020,17, 4825; doi:10.3390 /ijerph17134825 /journal/ijerph

Int. J. Environ. Res. Public Health2020,17, 4825 2 of 11 well as in the metabolic substrate are dependent of the performance level reached by the athlete [4,5]. The continuous training and the rational distribution of the training sessions would be the pillars to obtain the correct physiological modi cations in athletes. There are numerous training periodization models to reach this aim [6–12]: (i) the traditional periodization models, focused on long distance and low intensity training; (ii) block models, focused on concentrating training load in short time period to increase the organic adaptation, and (iii) the more recent training paradigm based on high intensity and low volume training called reverse periodization (RP). RP, unlike previous periodization models, begin the macrocycle with high-intensity and low-volume training, while gradually decreasing intensity and increasing volume or, depending on the sport, maintaining intensity and increasing volume during the following training periods [13]. This recent training paradigm has been previously studied in physical tness, strength training, swimming, triathlon and rowing, obtaining increases in muscular endurance, maximum strength, and endurance performance [10,13,14]. The increases in performance associated with the RP are closely related with the use of high intensity training, especially with methodology like high intensity interval training [7]. These short-term training methodologies have been reported as e cient interventions to increase sympathetic modulation to achieve di erent physiological adaptions related with aerobic performance such as the increase in muscle bu ering capacity, glycogen content, GLUT4 concentration, and maximal glucose transport activity in skeletal muscle [15–18]. In addition, RP improves jump performance in endurance athletes, but traditional periodization a ects it negatively [13]. Finally, hematological parameters might be in uenced by long-term training and competition periods decreasing during the intense periods of training throughout the season [18]. However, the e ect of periodized training, and speci cally, the in uence of this new training periodization model (i.e., reverse periodization) on chemical parameters and physiological adaptations are still poorly known, especially in the running collective. For this reason, we proposed the present research with the aim to analyze the e ect of 12 weeks of a Block Periodization

However, the e ect of periodized training, and speci cally, the in uence of this new training periodization model (i.e., reverse periodization) on chemical parameters and physiological adaptations are still poorly known, especially in the running collective. For this reason, we proposed the present research with the aim to analyze the e ect of 12 weeks of a Block Periodization and a Reverse Periodization on hematological parameters, countermovement jump, and aerobic (measured in a treadmill test and a 10 km time trial test) and anaerobic running performance of trained athletes. The initial hypothesis was that reverse training periodization would achieve a higher running performance and a signi cant modi cation in hematological parameters than block training periodization. 2. Materials and Methods 2.1. Design To test the e ects of 12 weeks of the two types of periodization training programs (reverse vs. block periodization) on hematological variables, aerobic and anaerobic running performance, and countermovement jump, a single-blinded randomized controlled (participant did not know the periodization model they were performing) trial with a pre- and post-test was conducted. Athletes were randomly divided into two experimental groups: (a) the reverse periodization (rp) group, who performed 4-weeks of high intensity training, 4-weeks of high volume training, and 4-weeks of tapering (n=8); and (b) the block periodization (bp) group, who performed 4-weeks of high volume training (accumulation), 4-weeks of high intensity training (transformation), and 4-weeks of tapering (realization) (n=8). 2.2. Participants Sixteen amateur athletes (eight males: 40.0 6.2 years; 179.2 12.8 cm; 73.8 12.2 kg; and eight females: 34.2 4.1 years; 163.4 9.6 cm; 57.0 11.0 kg; six training sessions/week; 42.4 12.4 min/session; 4.3 0.4 h of training/week;>6 year of experience on running training; competing at regional and national level in 10 km and half-marathon races) participated in this study. None of the participants had any musculoskeletal disorders. Before the testing sessions, participants were divided, in randomized order, into either the RP (n=8; four males and four females; age: 37.0 9.2 years; height: 170.2 19.2 cm;

races) participated in this study. None of the participants had any musculoskeletal disorders. Before the testing sessions, participants were divided, in randomized order, into either the RP (n=8; four males and four females; age: 37.0 9.2 years; height: 170.2 19.2 cm;

Int. J. Environ. Res. Public Health2020,17, 4825 3 of 11 weight: 65.8 10.2 kg) or BP (n=8; four males and four females; age: 37.2 5.7 years; height: 172.4 9.1 cm; weight: 65.1 10.4 kg) groups. The study design and the procedures employed were in accordance with ethical standards and the Declaration of Helsinki (1964). Each participant was fully informed of the risks associated with the study and provided written informed consent before starting the study. The present research was approved by the Catholic University of Murcia Ethics Committee (REF: CE071902). 2.3. Testing Protocol The assessments were carried out on two di erent days, separated by 48 h, in both the pre- and post-test and at the same time of the day in both evaluations. Pre- and post-tests were carried out 72 h after the last intense workout to allow complete recovery from training. On the rst day, athletes visited the laboratory to conduct a blood test, a running-based anaerobic sprint test (RAST), and a treadmill running test. The second testing session was performed 72 h after the rst testing session on an o cial athletics track and included Countermovement Jump (CMJ) and the 10 km time trial test. On the day after the training program nished, the same testing procedures were applied. In addition, a nutritionist performed an initial prospective 24-h dietary recall to assess the participants' diets. Afterward, a 7-day food record with qualitative and quantitative data, along with a printed guide for proper lling, was given to the participants to calculate their daily average intake through the rst week of the training program, and calculated using software (Cronometer Software Inc., https://cronometer.com, V.1.) [ 19]. This nutritional assessment was performed again when the training program nished and no di erences were observed between the periodization models and moments. 2.4. Blood Sample Collection The blood sample (2.5 mL) was withdrawn from an antecubital vein using a sterile technique to analyze hematological variables. Blood samples were taken before breakfast after an overnight fast. Blood extraction was performed with the subject seated. Erythrocytes ( 10 6 /L), hematocrit (%), hemoglobin (g/dL), ferritin

erences were observed between the periodization models and moments. 2.4. Blood Sample Collection The blood sample (2.5 mL) was withdrawn from an antecubital vein using a sterile technique to analyze hematological variables. Blood samples were taken before breakfast after an overnight fast. Blood extraction was performed with the subject seated. Erythrocytes ( 10 6 /L), hematocrit (%), hemoglobin (g/dL), ferritin (g/L), glucose (mg/dL), and triglycerides (mg/dL) were assessed. 2.5. Running-Based Anaerobic Sprint Test (RAST) The RAST consisted of six maximal e orts of 35-m, separated by a passive recovery of 10 s. The athlete started 0.5 m behind the start line, which was marked by a photocell (Witty, Microgate, Italy) [20]. Before starting, the athletes were instructed to run as fast as possible to the end of the 35 m course. Before testing, a warm-up consisting of 5 min of jogging followed by active stretching and two short duration submaximal sprints was performed. Following each sprint, athletes decelerated and walked to the starting line ready for the subsequent sprint. The best and mean sprint time were recorded as the performance indices. Verbal encouragement was given to the participants to ensure maximum physical e ort. 2.6. Treadmill Running Test Thirty minutes after RAST test, runners completed an incremental test to exhaustion on a treadmill (Run MedTechnogym, Cessena, Italy) in standard environmental conditions with the grade set at 1%. The tests were performed between 10:30 and 12:00 a.m. in the laboratory with the room temperature set between 20 –22 C and 45–50% of humidity. The gas analyzer system was calibrated before each test following the manufacturer's recommendations. During testing, gas exchange was measured using a breath-by-breath gas analyzer (Metalyzer 3B; Cortex-medical, Leipzig, Germany). Expired minute volume (VE), oxygen consumption (VO2), and carbon dioxide production (VCO2) were continuously recorded and averaged each minute. The respiratory exchange ratio (R=VCO2/VO2), the O2ventilatory equivalent (VE/VO2) and the CO2ventilatory equivalent (VE/VCO2) were calculated. Athletes started running at 8 km/h for 5 min. Subsequently, the work rate was increased by 0.5 km/h every 30 s in a progressive manner until exhaustion for optimal determination of VT2 and VO2max.

dioxide production (VCO2) were continuously recorded and averaged each minute. The respiratory exchange ratio (R=VCO2/VO2), the O2ventilatory equivalent (VE/VO2) and the CO2ventilatory equivalent (VE/VCO2) were calculated. Athletes started running at 8 km/h for 5 min. Subsequently, the work rate was increased by 0.5 km/h every 30 s in a progressive manner until exhaustion for optimal determination of VT2 and VO2max.

Int. J. Environ. Res. Public Health2020,17, 4825 4 of 11 The corresponding heart rate was also determined by a validated Polar RS800CX heart rate monitor (Polar Electro, Kempele, Finland) [21]. Verbal encouragement was given to ensure maximum physical e ort. The test was concluded according to traditional physiological criteria when participants reached volitional fatigue [3]. After the test, Ventilatory Thresholds were determined as follows: T1 was de ned as the rst increase of VE/VO2vs. workload, without a simultaneous increase in VE/VCO2vs. workload; and VT2 was de ned as the second increase in VE with a concomitant rapid increase in VE/VO2and VE/VCO2and decrease of end-tidal CO2tension (PETCO2) [22]. 2.7. Countermovement Jump During the second testing day, athletes completed a 15 min warm-up, similar to those performed prior to a competitive event, which included the following components: jogging (easy pace-Z1), running technique, and progressive running to race-pace. After warm-up, participants executed two submaximal trials of CMJ to ensure proper execution of the jumps with 1 min of rest in between trials. Two minutes after the speci c warm-up to jump, participants started the CMJ test. For the CMJ execution, participants maintained 90 of knee exion during 5” while the researcher con rmed the 90 with a square. The CMJ heights were calculated using a contact platform (Ergotester, Globus, Codogne, Italy) [23]. The CMJ was performed at the center of the platform with the feet placed shoulder width apart in the standing position. Participants were asked to jump as high as possible with a rapid self-selected countermovement. Participants were asked to try and land close to the take-o point. Each participant performed two attempts, with 90 s of rest in between attempts. The best trial from each participant was used for data analysis. 2.8. Ten Kilometer Time Trial Test After the CMJ test, a 10-km time trial test was carried out on an o cial athletic track. The 10-km time was recorded using a Geonaute chronometer Onstart 710 (Decathlon, Villeneuve-d'Ascq, France) by two of the researchers and the mean of these values was used for analysis. 2.9. Training Program Two weeks before starting

2.8. Ten Kilometer Time Trial Test After the CMJ test, a 10-km time trial test was carried out on an o cial athletic track. The 10-km time was recorded using a Geonaute chronometer Onstart 710 (Decathlon, Villeneuve-d'Ascq, France) by two of the researchers and the mean of these values was used for analysis. 2.9. Training Program Two weeks before starting the training program, all participants performed the same two-familiarization weeks. During this stage, athletes completed three running sessions in Z1 and two strength workouts each week. Participants started the familiarization period after three weeks of detraining weeks or o -season period. After this initial training period, participants in both periodizations completed a 12-week training periodization program consisting of two strength workouts, ve running session, and one day of total rest per week. The RP group performed a 12-week periodization composed of a 4-week mesocycle based on high intensity and low volume training, a 4-week mesocycle based on high volume and intensity training, and a 4-week mesocycle based on modeling competition and tapering. The training intensity distribution was polarized in the rst mesocycle and pyramidal in the second and third. On the other hand, the BP group completed a 12-week periodization composed of 4-weeks of high volume training (accumulation), 4-weeks of high intensity training (transmutation), and 4-weeks of modeling competition and tapering (realization). In addition, we applied a polarized distribution in the second mesocycle and a pyramidal distribution in the rst and third. Training zones were classi ed, according to previous literature, in three training zones: zone 1 (Z1), low intensity training (Rated of Perceived Exertion, RPE 4); zone 2 (Z2), anaerobic threshold training (RPE 4–7); and zone 3 (Z3), high intensity training (RPE 7) [24]. To quantify the training load of each session conducted by the athletes during each week, we used the session-RPE method [25]. In this method, the training load is quanti ed by multiplying the whole training-session RPE using the 10-point Borg scale by its duration. This product represents the training impulse (TRIMP) or the magnitude of the internal training load in arbitrary units. The RPE was

of each session conducted by the athletes during each week, we used the session-RPE method [25]. In this method, the training load is quanti ed by multiplying the whole training-session RPE using the 10-point Borg scale by its duration. This product represents the training impulse (TRIMP) or the magnitude of the internal training load in arbitrary units. The RPE was recorded thirty minutes after every training session. An example of typical training series in each phase of the 12-week training period for both periodizations are shown in Table.

Int. J. Environ. Res. Public Health2020,17, 4825 5 of 11 Table 1. Examples of typical training series in each phase of the 12-week training period for both block and reverse training periodizations. Periodization Model Weeks 1–4 Weeks 5–8 Weeks 9–12 Block periodization 1 50 min Z1 3 2000 m/3 min Z2 6 1000 m/3 min Z3 2 (5 400 m/90 s)/8 min/Z3 10 1000 m/3 min Z3 Reverse periodization 10 200 m/2 min Z3 3 (10 100 m/30 s)/3 0 Z3 8 1000 m/2 min Z2 2 (10 300 m/90 s)/8 min Z3 10 1000 m/3 min Z3 Series (repetition distance or duration and intensity/recovery between repetitions)/recovery between series; Z1—Low intensity training; Z2—Threshold training; Z3—High intensity training. 2.10. Statistical Analysis Statistical analysis of data was performed with SPSS v 24.0 (Chicago, IL, USA) in the Windows environment. Descriptive data are presented as mean standard deviation (SD). For the inferential analysis, a Shapiro–Wilks W-Test was performed to establish the normality of the sampling distribution and Mauchly's W test to analyze the sphericity between measurements. In addition, a two-way (type of periodization time) analysis of variance (ANOVA) with repeated measures and Bonferroni post-hoc was used to investigate the di erences in the study variables. In addition, an unpaired sampleT-test was used to compare the training load of both periodization programs. Mean di erence and 95% con dence interval (95% CI) were included. The e ect size (ES) was calculated using partial ETA squared ( 2) in ANOVA. In addition, the d was calculated using Cohen's guidelines to compare the training load in each intervention (BP vs. RP) and to analyze the e ect of time using the threshold values of>0.2 (small),>0.6 (moderate),>1.2 (large), and>2.0 (very large) [26]. For all procedures, a level ofp 0.05 was selected to indicate statistical signi cance. 3. Results Table ect of periodization group time in the hematological variables. There was a main e ect of time on triglycerides (F=5.333; p=0.037; d=0.94) in RP. Table 2.Hematological results in both groups. Variables Pre-Training Post-Training 95% CI for Di erence Mean SD Mean SD ES p MD Lower Bound Upper

This study compares the effects of block and reverse training periodization on athletes' performance.