Effects of 12 weeks of block periodization on performance and performance indices in well-trained cyclists

The higher the fraction of maximal oxygen uptake is during interval training, the greater is the cycling performance gain

It has been suggested that time at a high fraction (%) of maximal oxygen uptake (VO2max) plays a decisive role for adaptations to interval training. Yet, no study has, to date, measured the % of VO2max during all interval sessions throughout a prolonged training intervention and subsequently related it to the magnitude of training adaptations. Thus, the present study aimed to investigate the relationship between % of VO2max achieved during an interval training intervention and changes in endurance performance and its physiological determinants in well-trained cyclists. Twenty-two cyclists (VO2max 67.1 (6.4) mL·min-1 ·kg-1; males, n = 19; females, n = 3) underwent a 9-week interval training intervention, consisting 21 sessions of 5 × 8-min intervals conducted at their 40-min highest sustainable mean power output (PO). Oxygen uptake was measured during all interval sessions, and the relationship between % of VO2max during work intervals and training adaptations were investigated using linear regression. A performance index was calculated from several performance measures. With higher % of VO2max during work intervals, greater improvements were observed for maximal PO during the VO2max test (R2 adjusted = 0.44, p = 0.009), PO at 4 mmol·L-1 [blood lactate] (R2 adjusted = 0.25, p = 0.035), the performance index (R2 adjusted = 0.36, p = 0.013), and VO2max (R2 adjusted = 0.54, p = 0.029). Other measures, such as % of maximal heart rate, were related to fewer outcome variables and exhibited poorer session-to-session repeatability compared to % of VO2max. In conclusion, improvements in endurance measures were positively related to the % of VO2max achieved during interval training. Percentage of VO2max was the measure that best reflected the magnitude of training adaptations.

Development of Specific Motor Skills through System Wall Bouldering Training: A Pilot Study

This study evaluated the effects of a five-week period of practicing specific climbing movements using a system wall on motor skills and bouldering performance compared to self-regulated, conventional bouldering. Thirteen advanced female boulderers (age: 24.5 ± 3.6 years, height: 166.9 ± 3.4 cm, and body mass: 63.4 ± 8.0 kg) were divided into an experimental group (n = 7) and a control group (n = 6). Both groups continued their normal training routines during the intervention, but the experimental group dedicated 30 minutes of their climbing time twice per week to practicing specific motor skills on a system climbing wall. Before and after the intervention, the participants attempted two boulder problems on the same wall. The performance was registered as the number of attempts to complete the boulder problems and as the highest hold reached within four attempts. Video recordings of climbers' best attempts, capturing the highest hold reached from a perspective directly behind them, were analyzed by three independent experts. The analysis was conducted using a five-point scale across six categories of movement quality. Modest enhancements in certain motor skills and performance were evident in both groups, revealing no significant distinction between them. The results underscore the efficacy of incorporating system walls into the training routines of advanced female boulder climbers, but the absence of between-group differences highlights the significance of individual preferences when choosing between conventional and system wall bouldering.

A training goal-oriented categorization model of high-intensity interval training

There are various categorization models of high-intensity interval training (HIIT) in the literature that need to be more consistent in definition, terminology, and concept completeness. In this review, we present a training goal-oriented categorization model of HIIT, aiming to find the best possible consensus among the various defined types of HIIT. This categorization concludes with six different types of HIIT derived from the literature, based on the interaction of interval duration, interval intensity and interval:recovery ratio. We discuss the science behind the defined types of HIIT and shed light on the possible effects of the various types of HIIT on aerobic, anaerobic, and neuromuscular systems and possible transfer effects into competition performance. We highlight various research gaps, discrepancies in findings and not yet proved know-how based on a lack of randomized controlled training studies, especially in well-trained to elite athlete cohorts. Our HIIT "toolbox" approach is designed to guide goal-oriented training. It is intended to lay the groundwork for future systematic reviews and serves as foundation for meta-analyses.

Training characteristics and performance of two male elite short-distance triathletes: From junior to "world-class"

OBJECTIVE

The sports-science literature lacks data on training and performance characteristics of international elite athletes over multiple seasons. The present case study provided general training characteristics and performance data of two male short-distance triathletes in the Junior, U23, and international Elite categories.

METHODS

General training and performance data of two male elite triathletes were described in swimming, cycling, and running segments from the 2015 to 2022 season. The training load was presented using the ECO model while the training intensity distribution (TID) was a triphasic model.

RESULTS

Both triathletes increased their performance throughout the seasons. Triathlete A increased his VO2max in cycling by 20.6%, in running by 16.7%. His power at VO2max and his speed at VO2max by 18.9% and 11.0%, respectively. Triathlete B improved his VO2max by 17.8% in cycling, by 16.1% in running and his power at VO2max by 24%, and his speed at VO2max by 14.3%. The triathletes trained on average 14-17 h a week. The TID model was polarized.

CONCLUSIONS

To achieve the top international level, it is necessary to consider the following measures: training load progression; improvements in physiological variables; and participation in international events starting from youth categories.

The Weekly Periodization of Top 5 Tour de France General Classification Finishers: A Multiple Case Study

PURPOSE

The aim of this study was to describe individual training characteristics, racing strategies, and periodization in preparation for the Tour de France in 2 world-class road cyclists finishing in the top 5 of the general classification.

METHODS

Week-by-week power meter training and racing data of 2 (A and B) road cyclists (age: 29 and 23 y; maximum oxygen consumption: 83 and 81 mL·min-1·kg-1; and relative 20-min record power output: 6.9 and 6.5 W·kg-1) in the preparation phase (December-July/August) leading up to the Tour de France were retrospectively analyzed. Weekly volume and intensity distribution in power zones were considered.

RESULTS

Cyclists A and B completed 46 and 19 races, 22.5 (6.3) and 18.2 (5.1) h·wk-1, with a pyramidal intensity distribution of 81.0%-13.3%-5.7%, and 88.8%-7.9%-3.3% in zone 1-zone 2-zone 3. Cyclist B spent 14 days at altitude. Increased high-intensity volume and polarization index occurred during race weeks. During periods without racing, training intensity progressively increased. Strength training was performed during November and December but not during the following months. During tapering, total exercise volume and time at high intensity decreased.

CONCLUSION

These data provide novel insights into the periodization of world-class road cyclists in advance of a top 5 placing in the Tour de France general classification.

The relationship between hemoglobin and [Formula: see text]: A systematic review and meta-analysis

OBJECTIVE

There is widespread agreement about the key role of hemoglobin for oxygen transport. Both observational and interventional studies have examined the relationship between hemoglobin levels and maximal oxygen uptake ([Formula: see text]) in humans. However, there exists considerable variability in the scientific literature regarding the potential relationship between hemoglobin and [Formula: see text]. Thus, we aimed to provide a comprehensive analysis of the diverse literature and examine the relationship between hemoglobin levels (hemoglobin concentration and mass) and [Formula: see text] (absolute and relative [Formula: see text]) among both observational and interventional studies.

METHODS

A systematic search was performed on December 6th, 2021. The study procedures and reporting of findings followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Article selection and data abstraction were performed in duplicate by two independent reviewers. Primary outcomes were hemoglobin levels and [Formula: see text] values (absolute and relative). For observational studies, meta-regression models were performed to examine the relationship between hemoglobin levels and [Formula: see text] values. For interventional studies, meta-analysis models were performed to determine the change in [Formula: see text] values (standard paired difference) associated with interventions designed to modify hemoglobin levels or [Formula: see text]. Meta-regression models were then performed to determine the relationship between a change in hemoglobin levels and the change in [Formula: see text] values.

RESULTS

Data from 384 studies (226 observational studies and 158 interventional studies) were examined. For observational data, there was a positive association between absolute [Formula: see text] and hemoglobin levels (hemoglobin concentration, hemoglobin mass, and hematocrit (P<0.001 for all)). Prespecified subgroup analyses demonstrated no apparent sex-related differences among these relationships. For interventional data, there was a positive association between the change of absolute [Formula: see text] (standard paired difference) and the change in hemoglobin levels (hemoglobin concentration (P<0.0001) and hemoglobin mass (P = 0.006)).

CONCLUSION

These findings suggest that [Formula: see text] values are closely associated with hemoglobin levels among both observational and interventional studies. Although our findings suggest a lack of sex differences in these relationships, there were limited studies incorporating females or stratifying results by biological sex.

Longitudinal haematological responses to training load and heat acclimation preceding a male team pursuit cycling world record

This study evaluated relationships between changes in training load, haematological responses, and endurance exercise performance during temperate and heat acclimation (HA) training preceding a male team cycling pursuit world record (WR). Haemoglobin mass (Hbmass) and concentration ([Hb]), plasma volume (PV) and blood volume (BV) were assessed in nine male track endurance cyclists (∼3 occasions per month) training in temperate conditions (247-142 days prior to the WR) to establish responses to differing acute (ATL) and chronic (CTL) training loads. Testing was performed again pre- and post-HA (22-28 days prior to the WR). Endurance performance (V̇O₂max, 4MMP, lactate threshold 1 and 2) was assessed on three occasions (238-231, 189-182 and 133-126 days prior to the WR). In temperate conditions, CTL was associated with Hbmass (B = 0.62, P = 0.02), PV (B = 4.49, P = 0.01) and BV (B = 6.51, P = 0.04) but not [Hb] (B = -0.01, P = 0.17). ATL was associated with PV (B = 2.28, P < 0.01), BV (B = 2.63, P = 0.04) and [Hb] (B = -0.01, P = 0.04) but not Hbmass (B = 0.10, P = 0.41). During HA, PV increased 8.2% (P < 0.01), while Hbmass, CTL and ATL were unchanged. Hbmass and [Hb] were associated with all performance outcomes (P < 0.05), except V̇O2max. PV and BV were not associated with performance outcomes. During temperate training, changes in Hbmass were most strongly associated with changes in CTL. Both CTL and ATL were associated with changes in PV, but HA was associated with increased PV and maintenance of Hbmass without increasing ATL or CTL. In practical terms, maintaining high CTL and high Hbmass might be beneficial for improving endurance performance.HIGHLIGHTSChanges in haemoglobin mass were associated with endurance exercise performance and changes in chronic training load in temperate conditions.Heat acclimation increased plasma volume and maintained haemoglobin mass independently of chronic training load.Chronic training loads and haemoglobin mass should be increased to improve endurance exercise performance.Heat acclimation may optimise haematological adaptations when training load is reduced.

VO2max (VO2peak) in elite athletes under high-intensity interval training: A meta-analysis

Consensus is lacking regarding whether high-intensity interval training (HIIT) effectively improves VO₂max (VO₂peak) in elite athletes (Athlete must be involved in regular competition at the national level). This meta-analysis compared the effects of HIIT and conventional training methods (continuous training, repeated-sprint training, high volume low-intensity training, high-intensity continuous running, sprint-interval training, moderate-intensity continuous training)on VO₂max in elite athletes. Nine studies were included, comprising 176 elite athletes (80 female). Compared to that with conventional training, VO₂max was significantly increased after HIIT (overall: 0.58 [0.30, 0.87], I² = 0.49, P = 0.03; males: 0.41 [0.06, 0.76], I² = 0%, P = 0.89). VO₂max had positive training effects when the HIIT recovery period had an interval time ≥2 min (0.44 [0.03, 0.84], I² = 0%, P = 0.99) and recovery phase intensity ≤40% (0.38 [0.05, 0.71], I² = 0%, P = 0.96). Thus, HIIT shows superiority over conventional training methods in improving VO₂max, promoting aerobic capacity, in elite athletes.

Training Periodization, Intensity Distribution, and Volume in Trained Cyclists: A Systematic Review

A well-planned periodized approach endeavors to allow road cyclists to achieve peak performance when their most important competitions are held.

PURPOSE

To identify the main characteristics of periodization models and physiological parameters of trained road cyclists as described by discernable training intensity distribution (TID), volume, and periodization models.

METHODS

The electronic databases Scopus, PubMed, and Web of Science were searched using a comprehensive list of relevant terms. Studies that investigated the effect of the periodization of training in cyclists and described training load (volume, TID) and periodization details were included in the systematic review.

RESULTS

Seven studies met the inclusion criteria. Block periodization (characterized by employment of highly concentrated training workload phases) ranged between 1- and 8-week blocks of high-, medium-, or low-intensity training. Training volume ranged from 8.75 to 11.68 h·wk-1 and both pyramidal and polarized TID were used. Traditional periodization (characterized by a first period of high-volume/low-intensity training, before reducing volume and increasing the proportion of high-intensity training) was characterized by a cyclic progressive increase in training load, the training volume ranged from 7.5 to 10.76 h·wk-1, and pyramidal TID was used. Block periodization improved maximum oxygen uptake (VO2max), peak aerobic power, lactate, and ventilatory thresholds, while traditional periodization improved VO2max, peak aerobic power, and lactate thresholds. In addition, a day-by-day programming approach improved VO2max and ventilatory thresholds.

CONCLUSIONS

No evidence is currently available favoring a specific periodization model during 8 to 12 weeks in trained road cyclists. However, few studies have examined seasonal impact of different periodization models in a systematic way.

Aerobic Training With Blood Flow Restriction for Endurance Athletes: Potential Benefits and Considerations of Implementation

ABSTRACT

Smith, NDW, Scott, BR, Girard, O, and Peiffer, JJ. Aerobic training with blood flow restriction for endurance athletes: potential benefits and considerations of implementation. J Strength Cond Res 36(12): 3541-3550, 2022-Low-intensity aerobic training with blood flow restriction (BFR) can improve maximal oxygen uptake, delay the onset of blood lactate accumulation, and may provide marginal benefits to economy of motion in untrained individuals. Such a training modality could also improve these physiological attributes in well-trained athletes. Indeed, aerobic BFR training could be beneficial for those recovering from injury, those who have limited time for training a specific physiological capacity, or as an adjunct training stimulus to provide variation in a program. However, similarly to endurance training without BFR, using aerobic BFR training to elicit physiological adaptations in endurance athletes will require additional considerations compared with nonendurance athletes. The objective of this narrative review is to discuss the acute and chronic aspects of aerobic BFR exercise for well-trained endurance athletes and highlight considerations for its effective implementation. This review first highlights key physiological capacities of endurance performance. The acute and chronic responses to aerobic BFR exercise and their impact on performance are then discussed. Finally, considerations for prescribing and monitoring aerobic BFR exercise in trained endurance populations are addressed to challenge current views on how BFR exercise is implemented.

How do world class top 5 Giro d'Italia finishers train? A qualitative multiple case study

The aim of this study was to describe individual training strategies in preparation to Giro d'Italia of three world class road cyclists who achieved a top 5 in the general classification. Day-to-day power meter training and racing data of three road cyclists (age: 26, 27, 25 years; relative maximum oxygen consumption: 81, 82, 80 ml·min^-1 ·kg^-1 ; relative 20-min record power output: 6.6, 6.6, 6.4 W kg^-1 ) of the 22 weeks (December-May) leading up to the top 5 in Giro d'Italia general classification were retrospectively analyzed. Weekly volume and intensity distribution were considered. Cyclists completed 17, 22, 29 races, trained averagely for 19.7 (7.9), 16.2 (7.0), 14.7 (6.2) hours per week, with a training intensity distribution of 91.3-6.5-2.2, 83.6-10.6-5.8, 86.7-8.9-4.4 in zone 1-zone 2-zone 3 before the Giro d'Italia. Two cyclists spent 55 and 39 days at altitude, one did not attend any altitude camp. Cyclists adopted an overall pyramidal intensity distribution with a relevant increase in high-intensity volume and polarization index in races weeks. Tapering phases seem to be dictated by race schedule instead of literature prescription, with no strength training performed by the three cyclists throughout the entire periodization.

A 6-day high-intensity interval microcycle improves indicators of endurance performance in elite cross-country skiers

Purpose

The aim of this study was to compare the effects of a 6-day high-intensity interval (HIT) block [BLOCK, n = 12, maximal oxygen uptake (V̇O2max = 69. 6 ± 4.3 mL·min−1·kg−1)] with a time-matched period with usual training (CON, n = 12, V̇O2max = 69.2 ± 4.2 mL·min−1·kg−1) in well-trained cross-country (XC) skiers on physiological determinants and indicators of endurance performance. Furthermore, the study aimed to investigate the acute physiological responses, including time ≥90% of V̇O2max, and its associated reliability during repeated HIT sessions in the HIT microcycle.

Methods

Before the 6-day HIT block and following 5 days of recovery after the HIT block, both groups were tested on indicators of endurance performance. To quantify time ≥90% of V̇O2max during interval sessions in the HIT block, V̇O2 measurements were performed on the 1st, 2nd, and last HIT session in BLOCK.

Results

BLOCK had a larger improvement than CON in maximal 1-min velocity achieved during the V̇O2max test (3.1 ± 3.1% vs. 1.2 ± 1.6%, respectively; p = 0.010) and velocity corresponding to 4 mmol·L−1 blood lactate (3.2 ± 2.9% vs. 0.6 ± 2.1%, respectively; p = 0.024). During submaximal exercise, BLOCK displayed a larger reduction in respiratory exchange ratio, blood lactate concentration, heart rate, and rate of perceived exertion (p &lt; 0.05) and a tendency towards less energy expenditure compared to CON (p = 0.073). The ICC of time ≥90% V̇O2max in the present study was 0.57, which indicates moderate reliability.

Conclusions

In well-trained XC skiers, BLOCK induced superior changes in indicators of endurance performance compared with CON, while time ≥90% of V̇O2max during the HIT sessions in the 6-day block had a moderate reliability.

Blood flow restriction during self-paced aerobic intervals reduces mechanical and cardiovascular demands without modifying neuromuscular fatigue

This study examined cardiovascular, perceptual, and neuromuscular fatigue characteristics during and after cycling intervals with and without blood flow restriction (BFR). Fourteen endurance cyclists/triathletes completed four 4-minute self-paced aerobic cycling intervals at the highest sustainable intensity, with and without intermittent BFR (60% of arterial occlusion pressure). Rest interval durations were six, four, and four minutes respectively. Power output, cardiovascular demands, and ratings of perceived exertion (RPE) were averaged over each interval. Knee extension torque and vastus lateralis electromyography responses following electrical stimulation of the femoral nerve were recorded pre-exercise, post-interval one (+1, 2, and 4-minutes) and post-interval four (+1, 2, 4, 6 and 8-minutes). Power output during BFR intervals was lower than non-BFR (233 ± 54 vs 282 ± 60W, p < 0.001). Oxygen uptake and heart rate during BFR intervals were lower compared to non-BFR (38.7 ± 4.5 vs 44.7 ± 6.44mL·kg^-1·min^-1, p < 0.001; 160 ± 14 vs 166 ± 10bpm, p < 0.001), while RPE was not different between conditions. Compared to pre-exercise, maximal voluntary contraction torque and peak twitch torque were reduced after the first interval with further reductions following the fourth interval (p < 0.001) independent of condition (p = 0.992). Voluntary activation (twitch interpolation) did not change between timepoints (p = 0.375). Overall, intermittent BFR reduced the mechanical and cardiovascular demands of self-paced intervals without modifying RPE or knee-extensor neuromuscular characteristics. Therefore, BFR reduced the cardiovascular demands while maintaining the muscular demands associated with self-paced intervals. Self-paced BFR intervals could be used to prevent cardiovascular and perceptual demands being the limiting factor of exercise intensity, thus allowing greater physiological muscular demands compared to intervals without BFR.

No Differences Between 12 Weeks of Block- vs. Traditional-Periodized Training in Performance Adaptations in Trained Cyclists

The purpose of this study was to compare the effects of 12 weeks load-matched block periodization (BP, n = 14), using weekly concentration of high- (HIT), moderate- (MIT), and low- (LIT) intensity training, with traditional periodization (TP, n = 16) using a weekly, cyclic progressive increase in training load of HIT-, MIT-, and LIT-sessions in trained cyclists (peak oxygen uptake: 58 ± 8 ml·kg⁻¹·min⁻¹). Red blood cell volume increased 10 ± 16% (p = 0.029) more in BP compared to TP, while capillaries around type I fibers increased 20 ± 12% (p = 0.002) more in TP compared to BP from Pre to Post12. No other group differences were found in time-trial (TT) performances or muscular-, or hematological adaptations. However, both groups improved 5 and 40-min TT power by 9 ± 9% (p < 0.001) and 8 ± 9% (p < 0.001), maximal aerobic power (W_max) and power output (PO) at 4 mmol·L⁻¹ blood lactate (W_4mmol), by 6 ± 7 (p = 0.001) and 10 ± 12% (p = 0.001), and gross efficiency (GE) in a semi-fatigued state by 0.5 ± 1.1%-points (p = 0.026). In contrast, GE in fresh state and VO_2peak were unaltered in both groups. The muscle protein content of β-hydroxyacyl (HAD) increased by 55 ± 58% in TP only, while both TP and BP increased the content of cytochrome c oxidase subunit IV (COXIV) by 72 ± 34%. Muscle enzyme activities of citrate synthase (CS) and phosphofructokinase (PFK) were unaltered. TP increased capillary-to-fiber ratio and capillary around fiber (CAF) type I by 36 ± 15% (p < 0.001) and 17 ± 8% (p = 0.025), respectively, while BP increased capillary density (CD) by 28 ± 24% (p = 0.048) from Pre to Post12. The present study shows no difference in performance between BP and “best practice”-TP of endurance training intensities using a cyclic, progressively increasing training load in trained cyclists. However, hematological and muscle capillary adaptations may differ.

Relationships Between Maximal Aerobic Speed, Lactate Threshold, and Double Poling Velocity at Lactate Threshold in Cross-Country Skiers

Purpose

To investigate the relationships between maximal aerobic speed (MAS), lactate threshold in per cent of peak oxygen uptake (LT) and velocity at LT (LT_v) in cross-country skiers. Secondly, we aimed to explore the fit of an equation previously used in cyclists and runners in a cohort of well-trained, competitive cross-country skiers for calculation of LT_v. Thirdly, we aimed to investigate if a new LT_v could still be calculated after a period of regular training only by providing a new MAS.

Methods

Ninety-five competitive cross-country skiers (65 males and 30 females) were tested for maximal oxygen uptake (VO_2max), peak oxygen uptake in double poling (DP-VO_2peak), oxygen cost of double poling (C_DP), LT, and LT_v. Thirty-five skiers volunteered to be tested 3 months later to evaluate potential changes in LT and LT_v.

Results

Velocity at LT was mainly determined by MAS (r = 0.88, p < 0.01). LT did not show a significant impact on LT_v. The product of MAS·LT precisely predicted LT_v at baseline (r = 0.99, SEE = 2.4%), and by only measuring MAS, a new LT_v could be accurately calculated (r = 0.92, SEE = 6.8%) 3 months later in a sub-set of the initial 95 skiers (n = 35).

Conclusion

The results suggest that LT has minor impact on LT_v in DP tested in a laboratory. LT_v seemed to be predominantly determined by MAS, and we suggest to put more focus on MAS and less on LT and LT_v in regular testing to evaluate aerobic performance capacity in DP.

How Do the Effects of an 8-Week Intervention Influence Subsequent Performance Development in Cross-Country Skiers?

PURPOSE

To investigate how the effects of increased low- versus high-intensity endurance training in an 8-week intervention influenced the subsequent development of performance and physiological indices in cross-country skiers.

METHODS

Forty-four (32 men and 12 women) junior cross-country skiers were randomly assigned into a low-intensity training group (LITG, n = 20) or high-intensity training group (HITG, n = 24) for an 8-week intervention followed by 5 weeks of standardized training with similar intensity distribution, and thereafter 14 weeks of self-chosen training. Performance and physiological indices in running and in roller-ski skating were determined preintervention, after the intervention, and after the standardized training period. Roller-ski skating was also tested after the period of self-chosen training.

RESULTS

No between-groups changes from preintervention to after the standardized training period were found in peak speed when incremental running and roller-ski skating (P = .83 and .51), although performance in both modes was improved in the LITG (2.4% [4.6%] and 3.3% [3.3%], P < .05) and in roller-ski skating for HITG (2.6% [3.1%], P < .01). While improvements in maximal oxygen consumption running and peak oxygen uptake roller-ski skating were greater in HITG than in LITG from preintervention to after the intervention, no between-groups differences were found from preintervention to after the standardized training period (P = .50 and .46), although peak oxygen uptake in roller-ski skating significantly improved in HITG (5.7% [7.0%], P < .01). No changes either within or between groups were found after the period of self-chosen training.

CONCLUSIONS

Differences in adaptations elicited by a short-term intervention focusing on low- versus high-intensity endurance training had little or no effect on the subsequent development of performance or physiological indices following a period of standardized training in cross-country skiers.

Comparison of Aerobic Capacity Changes as a Result of a Polarized or Block Training Program among Trained Mountain Bike Cyclists

This study compared the effectiveness of a block training program and a polarized training program in developing aerobic capacity in twenty trained mountain bike cyclists. The cyclists were divided into two groups: the block training program group (BT) and the polarized training program group (PT). The experiment lasted 8 weeks. During the experiment, the BT group alternated between 17-day blocks consisting of dominant low-intensity training (LIT) and 11-day blocks consisting of sprint interval training (SIT), and high-intensity interval training (HIIT), while the PT group performed SIT, HIIT, and LIT simultaneously. Before and after the experiment, the cyclists performed incremental tests during which maximal oxygen uptake (VO₂max), maximal aerobic power (Pmax), power achieved at the first ventilatory threshold (P_VT1), and at the second ventilatory threshold (P_VT2) were measured. VO₂max increased in BT group (from 3.75 ± 0.67 to 4.00 ± 0.75 L∙min^-1) and PT group (from 3.66 ± 0.73 to 4.20 ± 0.89 L∙min^-1). In addition, Pmax, P_VT1, and P_VT2 increased in both groups to a similar extent. In conclusion, the polarized training program was more effective in developing the VO₂max compared to the block program. In terms of developing other parameters characterizing the cyclists' aerobic capacity, the block and polarized program induced similar results.

Effects of Individual Changes in Training Distribution on Maximal Aerobic Capacity in Well-Trained Cross-Country Skiers: A Follow-Up Study

The purpose of this study was to evaluate individual changes in training distribution and the subsequent effects on maximal oxygen uptake (VO_2max). The participants were well-trained cross-country skiers who had performed a year with no substantial changes in training prior to this study. Six cross-country skiers, who were participants in a larger previous study, volunteered for a follow-up study. All skiers performed self-motivated changes in training distribution for a new preparation period in this follow-up, generally by more high-intensity training (HIT). All training characteristics were registered from training diaries. During the follow-up period, all skiers performed an incremental VO_2max test in February 2020 and August 2020. Training were categorized into three different training periods; (1) February 2019 to February 2020 (P₁) representing the training performed prior to the follow-up, (2) February 2020 to July 2020 (P₂), and (3) July 2020 to August 2020 (P₃). On average, the skiers increased their VO_2max by 5.8 ± 5.0% (range: −1.8 to + 10.2%) during the follow-up study compared with the average VO_2max during the preceding year. Total training volume increased on average by 10.0 and 25.7% in P₂ and P₃, respectively, compared with P₁. The average volume of HIT was similar between P₁ and P₂ but increased 62.8% in P₃. However, large individual differences in training changes were observed. In conclusion, the present study revealed that individual changes in training distribution generated an increased VO_2max in four out of six already well-trained cross-country skiers. Reduced total training volume (three out of six) and increased (four out of six) HIT volume were the most marked changes.

The Effects of Prioritizing Lead or Boulder Climbing Among Intermediate Climbers

This study compared the effects of prioritizing lead climbing or boulder climbing on climbing-specific strength and endurance, as well as climbing performance. Fourteen active climbers were randomized to a boulder climbing training group (BCT: age = 27.2 ± 4.4 years, body mass = 65.8 ± 5.5 kg, height = 173.3 ± 3.8 cm) or a lead-climbing training group (LCT: age = 27.7 ± 6.1 years, body mass = 70.2 ± 4.4 kg, height = 177.7 ± 4.4 cm). The groups participated in a 5-week training period consisting of 15 sessions, performing either two weekly bouldering sessions and one maintenance-session of lead-climbing (BCT) or two weekly lead-climbing sessions and one maintenance-session of bouldering (LCT). Pre- and post-training, maximal force and rate of force development (RFD) were measured during isometric pull-ups performed on a jug hold and a shallow rung, and during an isolated finger-strength test. Lead-climbing and bouldering performance were also measured, along with an intermittent forearm endurance test. The pre-to-post changes were not significantly different between the groups for any of the parameters (P = 0.062-0.710). However, both the BCT (ES = 0.30, P = 0.049) and LCT (ES = 0.41, P = 0.046) groups improved strength in the isometric pull-up performed using the jug, whereas neither group improved force in the rung condition (P = 0.054 and P = 0.084) or RFD (P = 0.060 and P = 0.070). Furthermore, climbing and bouldering performance remained unchanged in both groups (P = 0.210-0.895). The LCT group improved forearm endurance (ES = 0.55, P = 0.007), while the BCT group improved isolated finger strength (ES = 0.35, P = 0.015). In addition to isometric pull-up strength, bouldering can increase isolated finger strength while lead-climbing may improve forearm endurance. A 5-week period prioritizing one discipline can be safely implemented for advanced to intermediate climbers without risking declined performance in the non-prioritized discipline.

Time Spent Near V˙O2max During Different Cycling Self-Paced Interval Training Protocols

PURPOSE

Cyclists may increase exercise intensity by prolonging exercise duration and/or shortening the recovery period during self-paced interval training, which could impact the time spent near V˙O2max. Thus, the main objective of this study was to compare the time spent near V˙O2max during 4 different self-paced interval training sessions.

METHODS

After an incremental test, 11 cyclists (mean [SD]: age = 34.4 [6.2] y; V˙O2max=55.7 [7.4] mL·kg-1·min-1) performed in a randomized order 4 self-paced interval training sessions characterized by a work-recovery ratio of 4:1 or 2:1. Sessions comprised 4 repetitions of 4 minutes of cycling with 1 minute (4/1) or 2 minutes (4/2) of active recovery or 8 minutes of cycling with 2 minutes (8/2) or 4 minutes (8/4) of active recovery. Time spent at 90% to 94% (t90V˙O2max), ≥95% (t95V˙O2max), and 90% to 100% V˙O2max (tV˙O2max) was analyzed in absolute terms and relative to the total work duration. Power output, heart rate, blood lactate, and rating of perceived exertion were compared.

RESULTS

The 8/4 session provided higher absolute tV˙O2max and t95V˙O2max than 8/2 (P = .015 and .029) and 4/1 (P = .002 and .047). The 4/2 protocol elicited higher relative tV˙O2max (47.7% [26.9%]) and t95V˙O2max (23.5% [22.7%]) than 4/1 (P = .015 and .028) and 8/2 (P < .01). Session 4/2 (275 [23] W) elicited greater mean power output (P < .01) than 4/1 (261 [27] W), 8/4 (250 [25] W), and 8/2 (234 [23] W).

CONCLUSIONS

Self-paced interval training composed of 4-minute and 8-minute work periods efficiently elicit tV˙O2max, but protocols with a work-recovery ratio of 2:1 (ie, 4/2 and 8/4) could be prioritized to maximize tV˙O2max.

Superior Physiological Adaptations After a Microcycle of Short Intervals Versus Long Intervals in Cyclists

PURPOSE

To compare the effects of a 1-week high-intensity aerobic-training shock microcycle composed of either 5 short-interval sessions (SI; n = 9, 5 series with 12 × 30-s work intervals interspersed with 15-s recovery and 3-min recovery between series) or 5 long-interval sessions (LI; n = 8, 6 series of 5-min work intervals with 2.5-min recovery between series) on indicators of endurance performance in well-trained cyclists.

METHODS

Before and following 6 days with standardized training loads after the 1-week high-intensity aerobic-training shock microcycle, both groups were tested in physiological determinants of endurance performance.

RESULTS

From pretraining to posttraining, SI achieved a larger improvement than LI in maximal oxygen uptake (5.7%; 95% confidence interval, 1.3-10.3; P = .015) and power output at a blood lactate concentration of 4 mmol·L-1 (3.8%; 95% confidence interval, 0.2-7.4; P = .038). There were no group differences in changes of fractional use of maximal oxygen uptake at a workload corresponding to a blood lactate concentration of 4 mmol·L-1, gross efficiency, or the 1-minute peak power output from the maximal-oxygen-uptake test.

CONCLUSION

The SI protocol may induce superior changes in indicators of endurance performance compared with the LI protocol, indicating that SI can be a good strategy during a 1-week high-intensity aerobic-training shock microcycle in well-trained cyclists.

Strength Training in Long-Distance Triathletes: Barriers and Characteristics

ABSTRACT

Luckin, KM, Badenhorst, CE, Cripps, AJ, Landers, GJ, Merrells, RJ, Bulsara, MK, and Hoyne, GF. Strength training in long-distance triathletes: Barriers and characteristics. J Strength Cond Res 35(2): 495-502, 2021-The purpose of this investigation was to identify perceived and physical barriers toward the completion of concurrent strength training and endurance training in long-distance triathletes. Three hundred ninety long-distance triathletes (224 women, 166 men; age [y]: 39 ± 10) completed a 68-question self-administered, semiquantitative survey that assessed endurance and strength training characteristics, experience in triathlon, and perceived barriers regarding the completion of strength training. Mean training hours per week was 14.92 ± 5.25, with 54.6% reporting participation in strength training. Heavy strength training was the most commonly reported (39.4%), with significantly more men completing this form of strength training (p < 0.001). Results from subjects who did not complete strength training indicated that perceived time constraints (53.1%) in addition to lack of knowledge on exercise progression and form (52.5%) are prominent perceived barriers to strength training completion. Identification of the barriers perceived by long-distance triathletes that prevent them from completing concurrent strength training and endurance training may be useful for coaches, athletes, and sports scientists who seek to incorporate strength training for injury prevention and performance improvement.

Periodization: Variation in the Definition and Discrepancies in Study Design

Over the past several decades, periodization has been widely accepted as the gold standard of training theory. Within the literature, there are numerous definitions for periodization, which makes it difficult to study. When examining the proposed definitions and related studies on periodization, problems arise in the following domains: (1) periodization has been proposed to serve as the macro-management of the training process concerning the annual plan, yet research on long-term effects is scarce; (2) periodization and programming are being used interchangeably in research; and (3) training is not periodized alongside other stressors such as sport (i.e., only resistance training is being performed without the inclusion of sport). Overall, the state of the literature suggests that the inability to define periodization makes the statement of its superiority difficult to experimentally test. This paper discusses the proposed definitions of periodization and the study designs which have been employed to examine the concept.

No Change - No Gain; The Effect of Age, Sex, Selected Genes and Training on Physiological and Performance Adaptations in Cross-Country Skiing

The aim was to investigate the effect of training, sex, age and selected genes on physiological and performance variables and adaptations before, and during 6 months of training in well-trained cross-country skiers. National-level cross-country skiers were recruited for a 6 months observational study (pre - post 1 - post 2 test). All participants were tested in an outside double poling time trial (TT_DP), maximal oxygen uptake in running (RUN-VO_2max), peak oxygen uptake in double poling (DP-VO_2peak), lactate threshold (LT) and oxygen cost of double poling (C_DP), jump height and maximal strength (1RM) in half squat and pull-down. Blood samples were drawn to genetically screen the participants for the ACTN3 R577X, ACE I/D, PPARGC1A rs8192678, PPARG rs1801282, PPARA rs4253778, ACSL1 rs6552828, and IL6 rs1474347 polymorphisms. The skiers were instructed to train according to their own training programs and report all training in training diaries based on heart rate measures from May to October. 29 skiers completed all testing and registered their training sufficiently throughout the study period. At pre-test, significant sex and age differences were observed in TT_DP (p < 0.01), DP-VO_2peak (p < 0.01), C_DP (p < 0.05), MAS (p < 0.01), LT_v (p < 0.01), 1RM half squat (p < 0.01), and 1RM pull-down (p < 0.01). For sex, there was also a significant difference in RUN-VO_2max (p < 0.01). No major differences were detected in physiological or performance variables based on genotypes. Total training volume ranged from 357.5 to 1056.8 min per week between participants, with a training intensity distribution of 90-5-5% in low-, moderate- and high-intensity training, respectively. Total training volume and ski-specific training increased significantly (p < 0.05) throughout the study period for the whole group, while the training intensity distribution was maintained. No physiological or performance variables improved during the 6 months of training for the whole group. No differences were observed in training progression or training adaptation between sexes or age-groups. In conclusion, sex and age affected physiological and performance variables, with only a minor impact from selected genes, at baseline. However, minor to no effect of sex, age, selected genes or the participants training were shown on training adaptations. Increased total training volume did not affect physiological and performance variables.

Influence of Interval Training Frequency on Time-Trial Performance in Elite Endurance Athletes

PURPOSE

To determine the impact of interval training frequency in elite endurance athletes. It was hypothesized that two longer sessions would elicit greater performance improvements and physiological adaptation than four shorter sessions at the same intensity.

METHODS

Elite cross-country skiers and biathletes were randomly assigned to either a high-frequency group (HF group) (5 M, 1 F, age 22 (19-26), VO_2max 67.8 (65.5-70.2) mL/kg/min) doing four short interval sessions per week or a low-frequency group (LF group) (8 M, 1 F, age 22 (18-23), VO_2max 70.7 (67.0-73.9) mL/kg/min) doing two longer interval sessions. All interval sessions were performed at ~85% of maximum heart rate, and groups were matched for total weekly training volume. Pre- and post-intervention, athletes completed an 8 km rollerski time-trial, maximal oxygen uptake (VO_2max) test, and an incremental, submaximal exercise test.

RESULTS

The LF group had a statistically significant improved time-trial performance following the intervention (p = 0.04), with no statistically significant changes in the HF group. Similarly, percentage utilization of VO_2max at anaerobic threshold (p = 0.04) and exercise economy (p = 0.01) were statistically significantly improved following the intervention in the LF group only. No statistically significant changes in VO_2max were observed in either group.

CONCLUSIONS

Two longer interval sessions appear superior to four shorter sessions per week in promoting endurance adaptations and performance improvements in elite endurance athletes. Despite matched training volume and exercise intensity, the larger, more concentrated exercise stimulus in the LF group appears to induce more favorable adaptations. The longer time between training sessions in the LF group may also have allowed athletes to recover more effectively and better "absorb" the training. These findings are in line with the "best practice" observed by many of the world's best endurance athletes.

Superior performance improvements in elite cyclists following short-interval vs effort-matched long-interval training

The purpose of this study was to compare the effects of 3 weeks with three weekly sessions (ie, nine sessions in total) of short intervals (SI; n = 9; 3 series with 13 × 30-second work intervals interspersed with 15-second recovery and 3-minutes recovery between series) against effort-matched (rate of perceived effort based) long intervals (LI; n = 9; 4 series of 5-minute work intervals with 2.5-minutes recovery between series) on performance parameters in elite cyclists ( V ˙ O 2max 73 ± 4 mL min^-1  kg^-1 ). There were no differences between groups in total volume and intensity distribution of training during the intervention period. SI achieved a larger (P < .05) relative improvement in peak aerobic power output than LI (3.7 ± 4.3% vs -0.3 ± 2.8%, respectively), fractional utilization of V ˙ O 2max at 4 mmol L^-1 [La^- ] (3.0 ± 5.8 percent points vs -3.5 ± 2.7 percent points, respectively), and larger relative increase in power output at 4 mmol L^-1 [La^- ] (2.0 ± 6.7% vs -2.8 ± 3.4, respectively), while there was no group difference in change of V ˙ O 2max . Improvements in performance measured as mean power output during 20-minute cycling test were greater (P < .01) in SI compared with LI (4.7 ± 4.4% vs -1.4 ± 2.2%, respectively). Mean effect size of the improvement in the above variables revealed a small to large effect of SI training vs LI training. The data thus demonstrate that the present SI protocol induces superior training adaptations compared with the present LI protocol in elite cyclists.

Block periodization of endurance training - a systematic review and meta-analysis

Background

Block periodization (BP) has been proposed as an alternative to traditional (TRAD) organization of the annual training plan for endurance athletes.

Objective

To our knowledge, this is the first meta-analysis to evaluate the effect BP of endurance training on endurance performance and factors determinative for endurance performance in trained- to well-trained athletes.

Methods

The PubMed, SPORTdiscus and Web of Science databases were searched from inception to August 2019. Studies were included if the following criteria were met: 1) the study examined a block-periodized endurance training intervention; 2) the study had a one-, two or multiple group-, crossover- or case-study design; 3) the study assessed at least one key endurance variable before and after the intervention period. A total of 2905 studies were screened, where 20 records met the eligibility criteria. Methodological quality for each study was assessed using the PEDro scale. Six studies were pooled to perform meta-analysis for maximal oxygen uptake (VO₂max) and maximal power output (Wmax) during an incremental exercise test to exhaustion. Due to a lower number of studies and heterogenous measurements, other performance measures were systematically reviewed.

Results

The meta-analyses revealed small favorable effects for BP compared to TRAD regarding changes in VO₂max (standardized mean difference, 0.40; 95% CI=0.02, 0.79) and Wmax (standardized mean difference, 0.28; 95% CI=0.01, 0.54). For changes in endurance performance and workload at different exercise thresholds BP generally revealed moderate- to large-effect sizes compared to TRAD.

Conclusion

BP is an adequate, alternative training strategy to TRAD as evidenced by superior training effects on VO₂max and Wmax in athletes. The reviewed studies show promising effects for BP of endurance training; however, these results must be considered with some caution due to small studies with generally low methodological quality (mean PEDro score =3.7/10).

Effects of whole-body vibration training frequency on neuromuscular performance: a randomized controlled study

This study compared the efficacy of two whole-body vibration (WBV) protocols with equal training volume and different frequency of training sessions/week on body composition and physical fitness. Sixty male air force cadets (age: 20.5±1.4 years) were randomly assigned to a lower frequency (Lf-WBV), a higher frequency (Hf-WBV) or a control group (CG). The training volume was equated (20 training sessions) between the two WBV groups, but the number of weekly training sessions was different. The Lf-WBV group trained three times per week, the Hf-WBV group trained five times per week, while the CG did not perform any training. Each training session, for both groups, included 10 sets x 1 min with 1 min rest of WBV on a synchronous vibration platform (25-35 Hz, 4-6 mm). Body composition, flexibility, maximal strength, 30 m sprint time, squat jump (SJ) and countermovement jump (CMJ) performance, Wingate test performance, and 20 m shuttle run performance were evaluated before and after training. Only the Hf-WBV group demonstrated an increase in flexibility (+7%; p<0.01; d=0.33) and maximal strength (+10%; p=0.016; d= 0.59), and a significant reduction in fat mass (-6.2%; p<0.01; d=0.21). SJ performance improved to a similar extent in both Hf-WBV and Lf-WBV groups (+7%; p<0.01; d=0.32). There were no changes in any parameter in the CG. In conclusion, only the condensed weekly WBV protocol was effective in improving body composition, flexibility, lower limb strength and power in young active individuals. The WBV protocol with the higher dispersion of training sessions per week (lower training frequency/week) improved SJ performance but did not have any effect on body composition, flexibility, or maximal strength.

A 11-day compressed overload and taper induces larger physiological improvements than a normal taper in elite cyclists

Endurance athletes usually achieve performance peaking with 2-4 weeks of overload training followed by 1-3 weeks of tapering. With a tight competition schedule, this may not be appropriate. Thus, the aim of this study was to compare the effect of a compressed variant of the recommended overload and tapering approach (EXP; n = 9, VO_2peak  = 77 ± 5 mL·min^-1 ·kg^-1 ) with a 11-day traditional taper that maintained the usual frequency of high-intensity aerobic interval training (HIT) and reduced the duration of training at lower exercise intensity (TRAD, n = 8, VO_2peak  = 74 ± 4 mL·min^-1 ·kg^-1 ) on physiological and psychological variables of endurance performance. EXP performed a 6-day period with daily HIT followed by a 5-day step taper. Testing was performed before the intervention (pre), on the 7th (post-1), and on the 11th day of the intervention (post-2). From pre to post-2, EXP achieved a larger relative improvement than TRAD in VO_2peak (4.0 ± 3.7% vs 0.8 ± 1.8%, respectively, P = .041) and the 1-min peak power output from the VO_2peak test (5.0 ± 3.6% vs 0.9 ± 1.5%, respectively, P = .009) and had a tendency toward larger improvement in power output at a blood lactate concentration of 4 mmol∙L^-1 (P = .088) and peak isokinetic knee extension (P = .06). The effect size of the relative improvement in the endurance variables revealed a moderate-to-large effect of EXP vs TRAD. In conclusion, this study indicates that elite cyclists performing the present 11-day compressed performance peaking protocol consisting of a 6-day HIT overload followed by a 5-day step taper are superior to a 11-day taper only.

Physical Activity and Sports-Real Health Benefits: A Review with Insight into the Public Health of Sweden

Positive effects from sports are achieved primarily through physical activity, but secondary effects bring health benefits such as psychosocial and personal development and less alcohol consumption. Negative effects, such as the risk of failure, injuries, eating disorders, and burnout, are also apparent. Because physical activity is increasingly conducted in an organized manner, sport’s role in society has become increasingly important over the years, not only for the individual but also for public health. In this paper, we intend to describe sport’s physiological and psychosocial health benefits, stemming both from physical activity and from sport participation per se. This narrative review summarizes research and presents health-related data from Swedish authorities. It is discussed that our daily lives are becoming less physically active, while organized exercise and training increases. Average energy intake is increasing, creating an energy surplus, and thus, we are seeing an increasing number of people who are overweight, which is a strong contributor to health problems. Physical activity and exercise have significant positive effects in preventing or alleviating mental illness, including depressive symptoms and anxiety- or stress-related disease. In conclusion, sports can be evolving, if personal capacities, social situation, and biological and psychological maturation are taken into account. Evidence suggests a dose–response relationship such that being active, even to a modest level, is superior to being inactive or sedentary. Recommendations for healthy sports are summarized.

Elite Swimmers' Training Patterns in the 25 Weeks Prior to Their Season's Best Performances: Insights Into Periodization From a 20-Years Cohort

Background

This study investigated the periodization of elite swimmers’ training over the 25 weeks preceding the major competition of the season.

Methods

We conducted a retrospective observational study of elite male (n = 60) and female (n = 67) swimmers (46 sprint, 81 middle-distance) over 20 competitive seasons (1992–2012). The following variables were monitored: training corresponding to blood lactate <2 mmol⋅L^-1, 2 to ≤4 mmol⋅L^-1, >4–6 mmol⋅L^-1, >6 mmol⋅L^-1, and maximal swimming speed; general conditioning and maximal strength training hours; total training load (TTL); and the mean normalized volumes for both in-water and dryland workouts. Latent class mixed modeling was used to identify various TTL pattern groups. The associations between pattern groups and sex, age, competition event, Olympic quadrennial year, training contents, and relative performance were quantified.

Results

For the entire cohort, ∼86–90% of the training was swum at an intensity of [La]_b ≤ 4 mmol⋅L^-1. This training volume was divided into 40–44% at <2 mmol⋅L^-1 and 44–46% at 2 to ≤4 mmol⋅L^-1, leaving 6–9.5% at >4–6 mmol⋅L^-1, and 3.5–4.5% at >6 mmol⋅L^-1. Three sprint TTL patterns were identified: a pattern with two long ∼14–15-week macrocycles, one with two ∼12–13 week macrocycles each composed of a balanced training load, and one with a single stable flat macrocycle. The long pattern elicited the fastest performances and was most prevalent in Olympic quadrennials (i.e., 4 seasons preceding the 2004, 2008, and 2012 Olympic Games). This pattern exhibited moderate week-to-week TTL variability (6 ± 3%), progressive training load increases between macrocycles, and more training at ≤4 mmol⋅L^-1 and >6 mmol⋅L^-1. This fastest sprint pattern showed a waveform in the second macrocycle consisting of two progressive load peaks 10–11 and 4–6 weeks before competition. The stable flat pattern was the slowest and showed low TTL variability (4 ± 3%), training load decreases between macrocycles (P < 0.01), and more training at 4–6 mmol⋅L^-1 (P < 0.01).

Conclusion

Progressive increases in training load, macrocycles lasting about 14–15 weeks, and substantial volume of training at intensities ≤4 mmol⋅L^-1 and >6 mmol⋅L^-1, were associated with peak performance in elite swimmers.

Block vs. Traditional Periodization of HIT: Two Different Paths to Success for the World's Best Cross-Country Skier

In short-term studies, block periodization of high-intensity training (HIT) has been shown to be an effective strategy that enhances performance and related physiological factors. However, long-term studies and detailed investigations of macro, meso, and micro-periodization of HIT blocks in world-class endurance athletes are currently lacking. In a recent study, we showed that the world’s most successful cross-country (XC) skier used two different periodization models with success throughout her career. One including extensive use of HIT blocks, namely BP, and one using a traditional method namely TRAD. In this study, we compare BP with TRAD in two comparable successful seasons and provide a detailed description of the annual use of HIT blocks in BP. The participant is the most-decorated winter Olympian, with 8 Olympic gold medals, 18 world championship titles, and 114 world cup victories. Training data was categorized by training form (endurance, strength, and speed), intensity [low (LIT), moderate (MIT), and HIT], and mode (running, cycling, and skiing/roller skiing). No significant difference was found in the total endurance training load between BP and TRAD. However, training volume in BP was lower compared to TRAD (15 ± 6 vs. 18 ± 7 h/wk, P = 0.001), mainly explained by less LIT (13 ± 5 vs. 15 ± 5 h/wk, P = 0.004). Lower volume of MIT was also performed in BP compared to TRAD (13 vs. 38 sessions/year), whereas the amount of HIT was higher in BP (157 vs. 77 sessions/year). While BP included high amounts of HIT already from the first preparation period, followed by a reduction toward the competition period, TRAD had a progressive increase in HIT toward the competition period. In BP, the athlete performed seven HIT blocks, varying from 7 to 11 days, each including 8–13 HIT sessions. This study provides novel insights into successful utilization of two different periodization models in the worlds best XC skier, and illustrates the macro, meso and micro- periodization of HIT blocks to increase the overall amount of HIT.

Adding vibration to high-intensity intervals increase time at high oxygen uptake in well-trained cyclists

The importance of accumulated time ≥90% of maximal oxygen consumption (VO_2max ) to improve performance in well-trained endurance athletes is well established. The present study compared the acute effects of adding vibrations (VIB; 40 Hz) with the work intervals during a high-intensity cycling session (HIT) with a traditional HIT session without vibration (TRAD) on time ≥90% of VO_2max , time ≥90% of peak heart rate (HR_peak ), electromyography (EMG) activity, and mean power in well-trained cyclists (n = 10, VO_2max =78.6 ± 7.4 mL/min/kg). The order of VIB and TRAD was randomized and consisted of 6 × 5-minutes work intervals performed with the highest possible mean power across the work intervals (2.5-minutes standardized relief periods). VIB was superior to TRAD on time ≥90% of VO_2max , (10.99 ± 7.00 vs 6.95 ± 5.28 minutes, respectively), time ≥90% of HR_peak (24.61 ± 2.38 vs 19.97 ± 4.12 minutes, respectively), and averaged EMG activity in m. Vastus Lateralis during the work intervals (all P < 0.05). The EMG/power output ratio across all work intervals was higher in VIB than TRAD (P < 0.05). Mean values across work intervals showed no difference between VIB and TRAD in mean power, rate of perceived exertion, or blood lactate concentration. Thus, the present study indicated that adding vibration to the work intervals during a HIT session can acutely increase the physiological responses of the cardiovascular system and increase time ≥90% VO_2max and should therefore be considered in order to optimize the exercise stimulus of well-trained cyclists.

The effect of a concentrated period of soccer-specific fitness training with small-sided games on physical fitness in youth players

BACKGROUND

It is unknown whether a concentrated period of small-sided games and high intensity training is an effective training approach in youth soccer players. The aim of the study was to examine the effect of a concentrated period of soccer specific training on physical fitness in youth players.

METHODS

Nineteen male soccer players, from two teams, participated (mean age: 16.2±0.8 years; body mass: 58.2±7.6 kg; height: 170.8±7.7 cm). One team performed 5 days of small-sided games and high intensity training (SSG & HIT; N.=12) and the other team regular soccer training with 1 day of SSG and HIT (REG; N.=7) weekly for 4 weeks. The 30-15 intermittent fitness test (30-15 IFT), countermovement jump (CMJ) and change of direction (COD) performance were measured pre and post intervention. Heart rate (HR) and rating of perceived exertion (RPE) were recorded and session load calculated (RPE x minutes).

RESULTS

Average percentage of maximum HR and session load were 83% and 344 AU for the SSG & HIT versus 73% and 253 AU for the REG (P<0.05). 30-15 IFT improved for the SSG & HIT (from 17.0±1.1 to 18.4±0.8 km/h; P<0.05; ES=0.57) with no difference for the REG group (Pre: 17.9±1.3, Post: 18.2±1.6 km/h, ES=0.10). CMJ and COD were unchanged in both groups and no injuries were reported.

CONCLUSIONS

A 4-week concentrated period of daily SSG & HIT is effective for improving endurance performance in youth soccer players. This was without injuries and without negating performance in power and change of direction.

An Integrated, Multifactorial Approach to Periodization for Optimal Performance in Individual and Team Sports

Sports periodization has traditionally focused on the exercise aspect of athletic preparation, while neglecting the integration of other elements that can impact an athlete's readiness for peak competition performances. Integrated periodization allows the coordinated inclusion of multiple training components best suited for a given training phase into an athlete's program. The aim of this article is to review the available evidence underpinning integrated periodization, focusing on exercise training, recovery, nutrition, psychological skills, and skill acquisition as key factors by which athletic preparation can be periodized. The periodization of heat and altitude adaptation, body composition, and physical therapy is also considered. Despite recent criticism, various methods of exercise training periodization can contribute to performance enhancement in a variety of elite individual and team sports, such as soccer. In the latter, both physical and strategic periodization are useful tools for managing the heavy travel schedule, fatigue, and injuries that occur throughout a competitive season. Recovery interventions should be periodized (ie, withheld or emphasized) to influence acute and chronic training adaptation and performance. Nutrient intake and timing in relation to exercise and as part of the periodization of an athlete's training and competition calendar can also promote physiological adaptations and performance capacity. Psychological skills are a central component of athletic performance, and their periodization should cater to each athlete's individual needs and the needs of the team. Skill acquisition can also be integrated into an athlete's periodized training program to make a significant contribution to competition performance.

A Scientific Approach to Improve Physiological Capacity of an Elite Cyclist

Previous studies in endurance athletes have indicated that block periodization (BP) can be a good alternative to the more traditional organization of training despite the fact that the total volume and intensity of the training are similar. However, these studies usually last only 4-12 wk. The aim of the present single-case study was to investigate the consequences of 58 wk with systematic BP of low-intensity training (LIT), moderate-intensity training (MIT), and high-intensity interval training (HIT) including incorporation of heavy strength training. It is important that a maintenance stimulus on the nonprioritized training modalities was added in the different training blocks. Performance-related variables were tested regularly during the intervention. The studied cyclist started with a maximal oxygen uptake (VO₂max) of 73.8 mL · kg^-1 · min^-1, peak aerobic power (W_max) of 6.14 W/kg, and a power output at 3 mmol/L blood lactate concentration (Power_3la-) of 3.6 W/kg. Total training volume during the 58-wk intervention was 678 h, of which 452 h were LIT (67%), 124 h were MIT (18%), 69 h were HIT (10%), and 34 h were heavy strength training (5%). The weekly training volume had a large range depending on the focus of the training block. After the intervention the cyclist's VO₂max was 87 mL · kg^-1 · min^-1, W_max was 7.35 W/kg, and Power_3la- was 4.9 W/kg. This single case indicates that the present training program can be a good alternative to the more traditional organization of long-term training of endurance athletes. However, a general recommendation cannot be given based on this single-case study.

Bench-to-Bedside Approaches for Personalized Exercise Therapy in Cancer

The past 2 decades have witnessed a growing body of work investigating the feasibility and efficacy of exercise therapy on a broad array of outcomes in many different oncology scenarios. Despite this heterogeneity, the exercise therapy prescription approach and the dose tested has been largely similar. Thus, current exercise therapy prescriptions in the oncology setting adopt a one-size-fits-all approach. In this article, we provide an overview of personalization of exercise therapy in cancer using the principles of training as an overarching framework. Specifically, we first review the fundamentals of exercise prescription in chronic disease before focusing attention on application of these principles to optimize the safety and efficacy of exercise therapy on (1) cancer treatment-induced cardiovascular toxicity and (2) tumor progression and metastasis.

Modelling of optimal training load patterns during the 11 weeks preceding major competition in elite swimmers

Periodization of swim training in the final training phases prior to competition and its effect on performance have been poorly described. We modeled the relationships between the final 11 weeks of training and competition performance in 138 elite sprint, middle-distance, and long-distance swimmers over 20 competitive seasons. Total training load (TTL), strength training (ST), and low- to medium-intensity and high-intensity training variables were monitored. Training loads were scaled as a percentage of the maximal volume measured at each intensity level. Four training periods (meso-cycles) were defined: the taper (weeks 1 to 2 before competition), short-term (weeks 3 to 5), medium-term (weeks 6 to 8), and long-term (weeks 9 to 11). Mixed-effects models were used to analyze the association between training loads in each training meso-cycle and end-of-season major competition performance. For sprinters, a 10% increase between ∼20% and 70% of the TTL in medium- and long-term meso-cycles was associated with 0.07 s and 0.20 s faster performance in the 50 m and 100 m events, respectively (p < 0.01). For middle-distance swimmers, a higher TTL in short-, medium-, and long-term training yielded faster competition performance (e.g., a 10% increase in TTL was associated with improvements of 0.1–1.0 s in 200 m events and 0.3–1.6 s in 400 m freestyle, p < 0.01). For sprinters, a 60%–70% maximal ST load 6–8 weeks before competition induced the largest positive effects on performance (p < 0.01). An increase in TTL during the medium- and long-term preparation (6–11 weeks to competition) was associated with improved performance. Periodization plans should be adapted to the specialty of swimmers.

The Physiological Capacity of the World's Highest Ranked Female Cross-country Skiers

Supplemental digital content is available in the text.

Purpose

The objective of this study is to compare the physiological capacity and training characteristics of the world’s six highest ranked female cross-country skiers (world class (WC)) with those of six competitors of national class (NC).

Methods

Immediately before the start of the competition season, all skiers performed three 5-min submaximal stages of roller skiing on a treadmill for measurement of oxygen cost, as well as a 3-min self-paced performance test using both the double poling (DP) and diagonal stride (DIA) techniques. During the 3-min performance tests, the total distance covered, peak oxygen uptake (V˙O_2peak), and accumulated oxygen deficit were determined. Each skier documented the intensity and mode of their training during the preceding 6 months in a diary.

Results

There were no differences between the groups with respect to oxygen cost or gross efficiency at the submaximal speeds. The WC skiers covered 6%–7% longer distances during the 3-min tests and exhibited average V˙O_2peak values of ∼70 and ∼65 mL·min⁻¹·kg⁻¹ with DIA and DP, respectively, which were 10% and 7% higher than the NC skiers (all P < 0.05). However, the accumulated oxygen deficit did not differ between groups. From May to October, the WC skiers trained a total of 532 ± 73 h (270 ± 26 sessions) versus 411 ± 62 h (240 ± 27 sessions) for the NC skiers. In addition, the WC skiers performed 26% more low-intensity and almost twice as much moderate-intensity endurance and speed training (all P < 0.05).

Conclusions

This study highlights the importance of a high oxygen uptake and the ability to use this while performing the different skiing techniques on varying terrains for female cross-country skiers to win international races. In addition, the training data documented here provide benchmark values for female endurance athletes aiming for medals.

The Effect of Different High-Intensity Periodization Models on Endurance Adaptations

PURPOSE

This study aimed to compare the effects of three different high-intensity training (HIT) models, balanced for total load but differing in training plan progression, on endurance adaptations.

METHODS

Sixty-three cyclists (peak oxygen uptake (V˙O2peak) 61.3 ± 5.8 mL·kg·min) were randomized to three training groups and instructed to follow a 12-wk training program consisting of 24 interval sessions, a high volume of low-intensity training, and laboratory testing. The increasing HIT group (n = 23) performed interval training as 4 × 16 min in weeks 1-4, 4 × 8 min in weeks 5-8, and 4 × 4 min in weeks 9-12. The decreasing HIT group (n = 20) performed interval sessions in the opposite mesocycle order as the increasing HIT group, and the mixed HIT group (n = 20) performed the interval prescriptions in a mixed distribution in all mesocycles. Interval sessions were prescribed as maximal session efforts and executed at mean values 4.7, 9.2, and 12.7 mmol·L blood lactate in 4 × 16-, 4 × 8-, and 4 × 4-min sessions, respectively (P < 0.001). Pre- and postintervention, cyclists were tested for mean power during a 40-min all-out trial, peak power output during incremental testing to exhaustion, V˙O2peak, and power at 4 mmol·L lactate.

RESULTS

All groups improved 5%-10% in mean power during a 40-min all-out trial, peak power output, and V˙O2peak postintervention (P < 0.05), but no adaptation differences emerged among the three training groups (P > 0.05). Further, an individual response analysis indicated similar likelihood of large, moderate, or nonresponses, respectively, in response to each training group (P > 0.05).

CONCLUSIONS

This study suggests that organizing different interval sessions in a specific periodized mesocycle order or in a mixed distribution during a 12-wk training period has little or no effect on training adaptation when the overall training load is the same.

No Additional Benefits of Block- Over Evenly-Distributed High-Intensity Interval Training within a Polarized Microcycle

Introduction: The current study aimed to investigate the responses to block- versus evenly-distributed high-intensity interval training (HIT) within a polarized microcycle.

Methods: Twenty well-trained junior cross-country skiers (10 males, age 17.6 ± 1.5 and 10 females, age 17.3 ± 1.5) completed two, 3-week periods of training (EVEN and BLOCK) in a randomized, crossover-design study. In EVEN, 3 HIT sessions (5 × 4-min of diagonal-stride roller-skiing) were completed at a maximal sustainable intensity each week while low-intensity training (LIT) was distributed evenly around the HIT. In BLOCK, the same 9 HIT sessions were completed in the second week while only LIT was completed in the first and third weeks. Heart rate (HR), session ratings of perceived exertion (sRPE), and perceived recovery (pREC) were recorded for all HIT and LIT sessions, while distance covered was recorded for each HIT interval. The recovery-stress questionnaire for athletes (RESTQ-Sport) was completed weekly. Before and after EVEN and BLOCK, resting saliva and muscle samples were collected and an incremental test and 600-m time-trial (TT) were completed.

Results: Pre- to post-testing revealed no significant differences between EVEN and BLOCK for changes in resting salivary cortisol, testosterone, or IgA, or for changes in muscle capillary density, fiber area, fiber composition, enzyme activity (CS, HAD, and PFK) or the protein content of VEGF or PGC-1α. Neither were any differences observed in the changes in skiing economy, V˙O2max or 600-m time-trial performance between interventions. These findings were coupled with no significant differences between EVEN and BLOCK for distance covered during HIT, summated HR zone scores, total sRPE training load, overall pREC or overall recovery-stress state. However, 600-m TT performance improved from pre- to post-training, irrespective of intervention (P = 0.003), and a number of hormonal and muscle biopsy markers were also significantly altered post-training (P < 0.05).

Discussion: The current study shows that well-trained junior cross-country skiers are able to complete 9 HIT sessions within 1 week without compromising total work done and without experiencing greater stress or reduced recovery over a 3-week polarized microcycle. However, the findings do not support block-distributed HIT as a superior method to a more even distribution of HIT in terms of enhancing physiological or performance adaptions.

The effects of block training on pacing during 20-km cycling time trial

The aim of this study was to determine the effects of block training (BL) on pacing during a 20-km hilly cycling time trial (TT) in trained cyclists. Twenty male cyclists were separated into 2 groups: control and BL. The training of each cyclist was monitored during a period of 3 weeks. In the first week cyclists performed an overload period of 7 consecutive days of high-intensity interval training followed by 2 weeks of normal training. Cyclists performed 1 TT before intervention and 2 TT after 7 and 14 days at the end of training. Each training session consisted of 10 sets of 3 repeated maximal-effort sprints (15, 30, and 45 s) with an effort/recovery duration ratio of 1:5. The main finding of this study was that the power output displayed a significantly higher start from the start until the halfway point of the TT (p < 0.05). Additionally, power output was characterized by a significant higher end spurt in the final 2 km in the BL after 2 weeks at the end of training (p < 0.05). In addition, after 2 weeks at the end of the overload period the distribution of cadence was significantly lower throughout the TT (p < 0.01). Therefore, a short period of consecutive days of intense training enhances cycling performance and changes the power output in the beginning and final part of the TT in trained cyclists.

Validity and Reliability of Ventilatory and Blood Lactate Thresholds in Well-Trained Cyclists

PURPOSE

The purpose of this study was to determine, i) the reliability of blood lactate and ventilatory-based thresholds, ii) the lactate threshold that corresponds with each ventilatory threshold (VT1 and VT2) and with maximal lactate steady state test (MLSS) as a proxy of cycling performance.

METHODS

Fourteen aerobically-trained male cyclists ([Formula: see text] 62.1±4.6 ml·kg-1·min-1) performed two graded exercise tests (50 W warm-up followed by 25 W·min-1) to exhaustion. Blood lactate, [Formula: see text] and [Formula: see text] data were collected at every stage. Workloads at VT1 (rise in [Formula: see text];) and VT2 (rise in [Formula: see text]) were compared with workloads at lactate thresholds. Several continuous tests were needed to detect the MLSS workload. Agreement and differences among tests were assessed with ANOVA, ICC and Bland-Altman. Reliability of each test was evaluated using ICC, CV and Bland-Altman plots.

RESULTS

Workloads at lactate threshold (LT) and LT+2.0 mMol·L-1 matched the ones for VT1 and VT2, respectively (p = 0.147 and 0.539; r = 0.72 and 0.80; Bias = -13.6 and 2.8, respectively). Furthermore, workload at LT+0.5 mMol·L-1 coincided with MLSS workload (p = 0.449; r = 0.78; Bias = -4.5). Lactate threshold tests had high reliability (CV = 3.4-3.7%; r = 0.85-0.89; Bias = -2.1-3.0) except for DMAX method (CV = 10.3%; r = 0.57; Bias = 15.4). Ventilatory thresholds show high reliability (CV = 1.6%-3.5%; r = 0.90-0.96; Bias = -1.8-2.9) except for RER = 1 and V-Slope (CV = 5.0-6.4%; r = 0.79; Bias = -5.6-12.4).

CONCLUSIONS

Lactate threshold tests can be a valid and reliable alternative to ventilatory thresholds to identify the workloads at the transition from aerobic to anaerobic metabolism.