A Systematic Review of Meta-Analyses Comparing Periodized and Non-periodized Exercise Programs: Why We Should Go Back to Original Research

Comparison of different periodization models on isotonic and isokinetic muscle strength and lean mass in tactical athletes

INTRODUCTION

Tactical athletes need to develop strength and lower limb lean mass (LL LM) to perform effectively. Resistance training (RT) is the most effective way to achieve these goals. Two periodization models stand out: traditional linear periodization (TLP) and daily undulating periodization (DUP).

OBJECTIVE

To verify the effect of lower limb RT with TLP and DUP on isotonic and isokinetic muscle strength and lean mass in tactical athletes.

METHOD

Thirty-five Brazilian Army military (21.57 ± 2.02 years; 81.81 ± 11.19 Kg; 177.79 ± 6.88 cm) were divided into two treatment groups and one active control group.

INTERVENTIONS

The treatment groups performed 9 weeks of supervised RT (18 sessions), consisting of free weight exercises in this order: back squat, squat lunge, deadlift, and stiff legged deadlift. Dynamic isotonic muscle strength, lean mass, and isokinetic knee extension and flexion were assessed at baseline and post treatment period.

RESULTS

There was a significant pre-post difference in dynamic isotonic muscle strength (TLP, P < 0.001; DUP, P < 0.001) and lean mass (TLP, P = 0.034; DUP, P = 0.003) of LL LM in both treatment groups. However, effect sizes (ES) and variations (%Δ) of gains were greater in the DUP group both in muscle strength (TLP, ES = 1.55, %Δ = 30.97; DUP, ES = 2.55, %Δ = 36.02), and in lean mass (TLP, ES = 0.13, %Δ = 2.07; DUP, ES = 0.44, %Δ = 2.95). For isokinetic knee flexion strength, a significant difference was found between the TLP versus CON.

CONCLUSION

Both lower limb RT periodization models provided gains in muscle strength and lean mass, with a small advantage for the DUP approach. In the isokinetic knee flexion strength, the TLP was more effective.

Coaches' Perceptions of Common Planning Concepts Within Training Theory: An International Survey

BACKGROUND

The planning of training is a popular yet controversial topic among coaches and sports scientists. Periodisation is often presented in the literature as the most efficacious approach to planning training. While historically surveys of coaches appeared to support this a key failing was that no unified definition of periodisation exists. Recent surveys offering a periodisation definition and an alternative planning methodology found many choosing the alternative therefore questioning periodisation's wide acceptance. The current survey looked to explore how coaches perceived specific concepts, drawn from the literature, that relate to the planning of training.

METHODS

106 coaches [age range: 18-65+ years, 31% 15+ years coaching, 58% individual-events/sports and 32% international level] from across the world completed a novel cross-sectional online survey on the planning of training and the training process. Topics included use of periodisation, division of time into discrete periods, assignment of goals and training to pre-determined periods and the adaptability of pre-established plans.

RESULTS

The majority described their planning approach as training periodisation (71%). Similarly, there was strong agreement with the necessity to determining a goal for the season (85%) and divide the season into distinct manageable periods of time (73%). When examining whether physical adaptations are achievable within specific and fixed timeframes only a minority (33%) agreed, a similar result was found for training physical capacities in a sequential order (37%). Finally, there was limited support for training targets remaining fixed over a training period (10%).

CONCLUSIONS

As a tool for the planning of athlete's training, periodisation is often presented as the best and most popular approach. Recent research however has highlighted possible discrepancies in its usage among practitioners. The results of this survey echo this and question the acceptance of periodisation concepts even among periodisation users. In part this may be due to key tenets of periodisation no longer being supported by research or practice. A lingering question then is whether the beliefs of coaches, developed through experience and supported by research, will continue to be marginalized. If sports scientists wish to aid coaches then they need to be engaged in future research initiatives as co-collaborators.

Maximizing Strength: The Stimuli and Mediators of Strength Gains and Their Application to Training and Rehabilitation

ABSTRACT

Spiering, BA, Clark, BC, Schoenfeld, BJ, Foulis, SA, and Pasiakos, SM. Maximizing strength: the stimuli and mediators of strength gains and their application to training and rehabilitation. J Strength Cond Res 37(4): 919-929, 2023-Traditional heavy resistance exercise (RE) training increases maximal strength, a valuable adaptation in many situations. That stated, some populations seek new opportunities for pushing the upper limits of strength gains (e.g., athletes and military personnel). Alternatively, other populations strive to increase or maintain strength but cannot perform heavy RE (e.g., during at-home exercise, during deployment, or after injury or illness). Therefore, the purpose of this narrative review is to (a) identify the known stimuli that trigger gains in strength; (b) identify the known factors that mediate the long-term effectiveness of these stimuli; (c) discuss (and in some cases, speculate on) potential opportunities for maximizing strength gains beyond current limits; and (d) discuss practical applications for increasing or maintaining strength when traditional heavy RE cannot be performed. First, by conceptually deconstructing traditional heavy RE, we identify that strength gains are stimulated through a sequence of events, namely: giving maximal mental effort, leading to maximal neural activation of muscle to produce forceful contractions, involving lifting and lowering movements, training through a full range of motion, and (potentially) inducing muscular metabolic stress. Second, we identify factors that mediate the long-term effectiveness of these RE stimuli, namely: optimizing the dose of RE within a session, beginning each set of RE in a minimally fatigued state, optimizing recovery between training sessions, and (potentially) periodizing the training stimulus over time. Equipped with these insights, we identify potential opportunities for further maximizing strength gains. Finally, we identify opportunities for increasing or maintaining strength when traditional heavy RE cannot be performed.

Strength and Conditioning Practices of Brazilian Olympic Sprint and Jump Coaches

Olympic coaches are likely to have adequate knowledge and implement effective training programs. This study aimed to describe and critically examine the strength and conditioning practices adopted by Brazilian Olympic sprint and jump coaches. Nineteen Olympic coaches (age: 50.2 ± 10.8 years; professional experience: 25.9 ± 13.1 years) completed a survey consisting of eight sections: 1) background information; 2) strength-power development; 3) speed training; 4) plyometrics; 5) flexibility training; 6) physical testing; 7) technology use; and 8) programming. It was noticed that coaches prioritized the development of explosiveness, power, and sprinting speed in their training programs, given the specific requirements of sprint and jump events. Nevertheless, unexpectedly, we observed: (1) large variations in the number of repetitions performed per set during resistance training in the off-season period, (2) a higher volume of resistance training prescribed during the competitive period (compared to other sports), and (3) infrequent use of traditional periodization models. These findings are probably related to the complex characteristics of modern competitive sports (e.g., congested competitive schedule) and the individual needs of sprinters and jumpers. Identification of training practices commonly used by leading track and field coaches may help practitioners and sport scientists create more effective research projects and training programs.

Flexible Training Planning Coupled with Flexible Assessment: A 12-Week Randomized Feasibility Study in a Youth Female Volleyball Team

According to the Quality Education and Gender Equality ambitions established at the 2030 Agenda for Sustainable Development Goals, we aimed to test the feasibility of a flexible planning and assessment process, using ongoing, bidirectional feedback between planning and assessment. Eighteen players (11.5 ± 0.5 years of age) from a U13 female volleyball team were randomized into an experimental group (in which the plan could be changed daily) or a contrast group (pre-defined planning, adjusted monthly). The pedagogical intervention lasted three months. Besides ongoing daily assessments from the training practices, the Game Performance Assessment Instrument was adopted as a starting point for the weekly assessments in 4 vs. 4 game-forms (i.e., the instrument was modified monthly based on feedback from the training process). Information from daily and weekly formal assessment was used in the planning of the experimental group, and monthly in the contrast group. Data suggested that pre-established and strict planning (even updated monthly) failed to fit current learner needs. Over 12 weeks, the pre-established planning suffered regular modifications in the experimental group, and the assessment tool changed monthly. In conclusion, both planning and assessment should be open and flexible to exchange information mutually, and support the design of tailor-made learning environments.

Ongoing Bidirectional Feedback between Planning and Assessment in Educational Contexts: A Narrative Review

Quality in education is one of the 17 goals in the United Nations' sustainable agenda for 2030, presupposing careful planning and assessment of learning. Traditional planning in sports education (either in training or school settings) largely adopts pre-determined learning sequences and temporal milestones that, in theory, enhance the learning process. However, learning is a context-dependent, non-linear process with considerable intra- and interindividual variability, whereby planning and assessment should also be non-linear. In this narrative review, the main findings suggest that the specific teaching or training contents and their relative (i.e., ordering or sequencing) and absolute timing (i.e., the specific time point where certain learning or adaptations are expected) should vary depending on the learners and the context. In a process-oriented perspective, this requires flexible planning and the establishment of ongoing bidirectional links between planning and assessment. In this framework, assessment should be a flexible, evolving, and daily pedagogical tool instead of a set of formal checkpoints. We further explored how planning and assessment could be linked to provide an ongoing feedback loop that respects the individuality of each learner and its context, and therefore hope this review helps bring about a change in current planning and assessment paradigms in sports education.

“I Want to Create So Much Stimulus That Adaptation Goes Through the Roof”: High-Performance Strength Coaches' Perceptions of Planned Overreaching

Functional overreaching (FOR) occurs when athletes experience improved athletic capabilities in the days and weeks following short-term periods of increased training demand. However, prolonged high training demand with insufficient recovery may also lead to non-functional overreaching (NFOR) or the overtraining syndrome (OTS). The aim of this research was to explore strength coaches' perceptions and experiences of planned overreaching (POR); short-term periods of increased training demand designed to improve athletic performance. Fourteen high-performance strength coaches (weightlifting; n = 5, powerlifting; n = 4, sprinting; n = 2, throws; n = 2, jumps; n = 1) participated in semistructured interviews. Reflexive thematic analysis identified 3 themes: creating enough challenge, training prescription, and questioning the risk to reward. POR was implemented for a 7 to 14 day training cycle and facilitated through increased daily/weekly training volume and/or training intensity. Participants implemented POR in the weeks (~5–8 weeks) preceding competition to allow sufficient time for performance restoration and improvement to occur. Short-term decreased performance capacity, both during and in the days to weeks following training, was an anticipated by-product of POR, and at times used as a benchmark to confirm that training demand was sufficiently challenging. Some participants chose not to implement POR due to a lack of knowledge, confidence, and/or perceived increased risk of athlete training maladaptation. Additionally, this research highlights the potential dichotomy between POR protocols used by strength coaches to enhance athletic performance and those used for the purpose of inducing training maladaptation for diagnostic identification.

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.

Resistance training, gremlin 1 and macrophage migration inhibitory factor in obese men: a randomised trial

OBJECTIVE

This study aimed to determine how different resistance training protocols affect gremlin 1, macrophage migration inhibitory factor (MIF), cardiometabolic, and anthropometric measures in obese men.

METHODS

Forty-four males with obesity (weight: 93.2 ± 2.2 kg, BMI: 32.9 ± 1.2 kg/m², age: 27.5 ± 9.4 years) were randomly assigned to traditional resistance training (TRT, n = 11), circuit resistance training (CRT, n = 11), interval resistance training (IRT, n = 11) or control (C, n = 11) groups. TRT group performed ten exercises at 50% of 1RM with 14 repetitions for three sets and 30 seconds rest interval between exercises and 1.5 min rest between sets, the CRT protocol included three circuits of 10 exercises, at an intensity of 50% of 1-RM, 14 repetitions with a minimum rest (< 15 s) between exercises and 3 min rest between sets, and the IRT group performed two sets of the same exercises with 50% of 1 RM, and 14 repetitions were followed with active rest of 25% of 1RM and 14 repetitions. All resistance training groups performed 60 min per session resistance exercises, 3 days per week, for 12 weeks. Measurements were taken at baseline and after 12 weeks of exercise training.

RESULTS

Resistance training (TRT, CRT, and IRT) significantly decreased plasma levels of gremlin (TRT from 231.0 ± 5.8 to 210.0 ± 11.6 ng/ml, CRT from 226.0 ± 7.6 to 188.0 ± 7.7 ng/ml and, IRT from 227.0 ± 6.3 to 183.0 ± 9.0 ng/ml, effect size (ES): 0.50), MIF (TRT from 251.0 ± 7.4 to 260.0 ± 6.5 ng/ml, CRT from 248.0 ± 10.9 to 214.0 ± 9.0 ng/ml and, IRT from 247.0 ± 8.9 to 196.0 ± 6.9 ng/ml, ES: 0.55) and CRP (TRT from 28.4 ± 1.7 to 23.3 ± 2.1 nmol/l, CRT from 28.5 ± 2.2 to 21.1 ± 1.8 nmol/l, IRT from 28.1 ± 1.3 to 20.8 ± 1.3 nmol/l, ES: 0.49) compared to the control group (p < .05), but these reduction were greater in the CRT and IRT groups compared to the TRT group (p < .05).

CONCLUSION

The CRT and IRT protocols had more beneficial improvement in gremlin 1, MIF, body composition, and cardiometabolic risk factors compared to the beneficial changes produced by TRT protocol.

A time and a place: A framework for caffeine periodization throughout the sporting year

Caffeine is a well-established ergogenic aid, with its performance-enhancing effects demonstrated across a variety of sports and exercise types. As a result of these ergogenic properties, caffeine is widely used by athletes at all levels around both competition and training. Caffeine exerts its performance benefits through a variety of mechanisms, each of which may be of increased importance at a given stage of training or competition. Additionally, regular caffeine use may diminish the performance-enhancing effects of a subsequent dose of caffeine. Recently, interest in the concept of nutritional periodization has grown. Here we propose a framework for the periodization of caffeine through the sporting year, balancing its training and competition performance-enhancing effects, along with the need to mitigate any negative effects of habituation. Furthermore, the regular use of caffeine within training may support the development of positive beliefs toward caffeine by athletes-potentially serving to enhance future performance through placebo and expectancy mechanisms-as well as allowing for the optimization of individual athlete caffeine strategies. Although future work is required to validate some of the suggestions made, the framework proposed here represents a starting point for athletes to maximize caffeine's performance benefits across the sporting year.

Towards a de facto Nonlinear Periodization: Extending Nonlinearity from Programming to Periodizing

Planning is paramount in sport. Among different philosophical approaches to planning, periodization is a highly popular concept that refers to structured training periods with ensuing programs encompassing moments of progressively-loaded training, followed by recovery; it is normally deemed paramount to optimize adaptations and performance. While planning provides generic guidelines, periodization refers to the sequencing/ordering of training periods to enforce a given plan, therefore referring to longer temporal scales, and programming refers to more micro-scale aspects. In fact, similar periodization schemes may implement distinct programming strategies. Literature on the topic has used the linear and nonlinear terms to describe the content of periodized programs. However, these concepts have not been clearly defined in the literature, which may lead to inaccurate and misleading interpretations. Moreover, nonlinear periodization is usually using nonlinear programming, but with pre-stipulated sequencing of the training periods. Finally, it can be argued that nonlinearity has been an integral part of periodization since its inception, at least theoretically. In this essay, the literature was critically reviewed to better understand the validity of the linearity and nonlinearity concepts as applied in currently proposed periodization models. In addition, a novel approach for a de facto nonlinear periodization is presented.