The effects of a 16-week periodized linear strength training program incorporating landmine exercises on physical performance in professional female volleyball players

Abstract

[Purpose]

The purpose of this study was to investigate the effects of a linear periodization training program combined with barbell-based landmine exercises on physical fitness factors related to performance enhancement in 18 female professional volleyball players.

[Methods]

The experiment was conducted over a 16-week linear periodization program, with participants assigned to either a Weight Training Group (WG, n = 9), which performed resistance training using weights, or a Weight plus Landmine Group (WLG, n = 9), which performed both resistance and landmine exercises. To evaluate improvements in physical fitness among elite athletes, measurements were taken for strength (deadlift, back squat), muscular endurance (sit-ups, push-up), and explosive power (countermovement jump). A paired t-test was performed to compare pre and post intervention results, and repeated two-way ANOVA was used to analyze the interaction effects between groups and time.

[Results]

The paired t-test results indicated that both groups showed significant improvements in deadlift, back squat, push-ups, countermovement jump (CMJ), and sit-ups. In particular, CMJ, which represents a volleyball-specific fitness component, showed significant between-group differences and group × time interaction effects in the landmine group.

[Conclusion]

Landmine exercises are considered effective for improving physical fitness in volleyball players, particularly by enhancing explosive power when incorporated into traditional linear periodization resistance training programs. These findings suggest that the application of landmine exercise programs in the field of sports may contribute to more effective improvements in athletic performance.

INTRODUCTION

Volleyball is recognized as one of the most popular sports worldwide, characterized by the repeated execution of high-intensity movements such as jumping, rapid directional changes, and spiking within short durations [1,2]. Owing to these sport-specific demands, anaerobic fitness components including muscular strength, explosive power, and agility have been reported to play a critical role in determining performance outcomes in volleyball athletes [3-5]. According to previous research, approximately 90% of the energy expenditure during volleyball matches is derived from anaerobic energy systems, with ~70% attributed to the ATP-PCr system and ~20% to glycolysis, whereas the aerobic system contributes only about 10% [5,6]. In particular, given the structure of volleyball matches characterized by rallies lasting an average of 1-10 seconds followed by recovery periods of 11-30 seconds the sport is classified as a representative high-intensity interval discipline. Consequently, systematic training programs targeting the anaerobic energy systems are essential for enhancing performance [7-9].

However, in practical training settings, strength training programs are still predominantly implemented based on personal experience and intuition rather than on systematic, evidence-based approaches [10]. Within this context, the design of scientific and systematic training programs grounded in the concept of periodization is essential for effectively enhancing volleyball players’ performance while minimizing excessive fatigue and injury during training [11,12]. Periodization not only enables a systematic approach to physical fitness development but is also recognized as an effective method for overcoming performance plateaus and achieving training goals in a progressive manner. In particular, traditional linear periodization, which is structured into macrocycles, mesocycles, and microcycles, is characterized by the progressive development of physical capacities over a given period, thereby promoting balanced improvements across all fitness components [13,14]. In line with this, previous studies have demonstrated the effectiveness of periodized strength training on performance outcomes. Crisp et al. [15] reported that a 16-week linear periodized strength training program improved vertical jump performance, while Voelzke et al. [16] observed significant enhancements in vertical jump ability following a 13-week periodized program consisting of three phases: general conditioning, hypertrophy, and maximal strength and power.

Meanwhile, in contemporary athletic training settings, various techniques have been introduced to optimize strength and power development. Among these, the landmine exercise a multi-joint compound movement performed by fixing one end of a barbell to the ground while holding and moving the opposite end has gained attention as an effective training method for enhancing core stability, rotational resistance, and hip-dominant movement control [17]. Particularly in volleyball, which involves frequent forward, backward, and rotational movements, compound exercises such as the landmine squat(Figure 1), landmine kneeling twist(Figure 2), landmine squat to press(Figure 3), landmine clean & jerk(Figure 4) requiring simultaneous hip and shoulder strength, joint stability, and trunk control may serve as an effective method for full body power development.

Figure 1. Landmine squat.

A. Stand with your feet shoulder-width apart, keep your chest open, and look straight ahead; B. Push your hips back, bend your knees to lower into the position, then rise back up.

Figure 2. Landmine kneeling twist.

A. Engage your core, then twist your torso and move the barbell over to the right side; B. Return to the center and assume a neutral position; C. Engage your core, then twist your torso and move the barbell over to the left side.

Figure 3. Landmine squat to press.

A. The barbell was positioned in front of the chest while maintaining a neutral posture; B. Participants performed the squat while holding the barbell in front of the body; C. The movement involved rising from the squat position followed by an overhead barbell press.

Figure 4. Landmine clean & jerk.

A. Grab the bar with the opposite hand, bend at the hips into a squat-like low position, keep the spine neutral, and open the chest; B. Cross your hands to grip the bar, then hold it securely in front of your chest; C. Slightly bend your knees, then quickly drive the bar overhead.

Despite the growing interest in periodized strength training and landmine exercises, few studies have investigated the combined effects of linear periodization-based strength programs with landmine exercises on the performance of volleyball players. In particular, no previous research has examined the impact of a mesocycle-based linear periodized training program incorporating landmine exercises on elite volleyball athletes. Therefore, the present study aims to analyze the effects of a 16-week training program that integrates traditional linear periodized weight training with barbell-based landmine compound exercises on the physical fitness components of elite female volleyball players, thereby providing evidence-based training strategies applicable to real-world athletic training settings.

METHODS

Participants

The participants were 21 female professional volleyball players from a professional team located in Region A. Prior to participation, all athletes were fully informed of the study’s objectives and procedures, and written voluntary consent was obtained. Three participants were excluded due to team transfers or musculoskeletal injuries during the study period, resulting in a final sample of 18 players. All participants were elite-level athletes who underwent training during the off-season, with consideration given to the sport-specific demands of volleyball. Using random assignment, subjects were divided into two groups: a Weight Training Group (WG) and a combined Weight Training plus Landmine Exercise Group (WLG). To assess physical characteristics including body weight, muscle mass, fat mass, and body fat percentage, body composition was measured using an InBody 720 analyzer (InBody 720; Biospace, Republic of Korea)(Table 1). All body composition tests (In-Body 720, Biospace, Korea) were performed in the morning after an overnight fast (≥ 8 h), participants refrained from strenuous exercise, alcohol and caffeine for 24 h, and avoided large fluid intake prior to testing. Repeated measures were collected pre- and post-intervention under the same conditions.

Table 1.

Subject physical characteristics.

Variables	Group	n	Mean ± SD
Weight (kg)	WLG	9	67.20 ± 8.39
	WG	9	67.14 ± 4.61
Muscle mass (kg)	WLG	9	30.62 ± 2.87
	WG	9	29.86 ± 2.41
Fat mass (kg)	WLG	9	12.90 ± 3.60
	WG	9	13.99 ± 2.49
BF (%)	WLG	9	18.92 ± 2.99
	WG	9	20.82 ± 3.38

WLG: weight + Landmine group; WG: weight group; BF: percent body fat;

^*p < .05;

^**p < .01;

^***p < .001.

Experimental Procedures

This study aimed to examine the effects of a 16-week linear periodized weight training program combined with landmine exercises on performance-related fitness factors in female professional volleyball players. Participants were randomly assigned to either the WG or the WLG by an investigator not involved in outcome testing using a computer-generated random number list; allocation was concealed in sealed opaque envelopes until assignments were revealed. The fitness variables assessed included maximal strength (deadlift, back squat), explosive power (counter movement jump), and muscular endurance (push-ups, sit-ups). Prior to the intervention, baseline assessments were conducted in the following order: muscular endurance, explosive power, and lower-body strength. Participants were assigned either to a linear periodized WG or to a group that performed the same program with the addition of WLG. After completing the prescribed 16-week training program, post-intervention measurements were conducted.

Measured Variables

The measurement protocols for the deadlift and back squat followed the guidelines of the National Strength & Conditioning Association (NSCA) and employed a direct testing method. To account for injury prevention and sport-specific considerations during the pre-season, the five-repetition maximum (5RM) test was used [18]. Prior to testing, participants performed a warm-up using a light load that could be lifted for more than 10 repetitions. After a 1-minute rest, the load was progressively increased by 10-20% over 3-5 repetitions until reaching near-maximal effort. Maximal loading attempts were performed after a 2-4-minute rest interval, and participants were encouraged to complete five repetitions at the highest achievable weight. Explosive power was assessed using the countermovement jump (CMJ). CMJ testing permitted an arm swing, with participants instructed to perform a maximal two-arm swing jump from a standing hip-width stance. Participants stood with their feet at hip width and performed a maximal jump utilizing both upper- and lower-body force. Jump height was recorded using a CMJ measurement device (VZJ-009S, MEILUJIE, Japan). Muscular endurance was evaluated through two tests: (1) the maximum number of push-ups(PU) completed in 30 seconds and (2) the maximum number of sit-ups(SU) performed within 1 minute. Participants performed as many standard push-ups as possible in 30 s with full elbow extension at the top and chest touching (or within ~5 cm of) the floor at the bottom; trunk alignment and technique were monitored by a test administrator. The SU test required participants to perform as many sit-ups as possible within 60 seconds, maintaining hips at a 90° angle and lifting the upper body until the elbows touched the knees. Only repetitions that met all technique criteria were counted as valid.

Exercise Program

The weight training program was implemented with reference to Arazi et al. [19], Marques et al. [20], while the landmine exercise program was adapted and refined based on guidelines from Otey et al. [21]. Exercise intensity and frequency were structured according to the principles of linear periodization and organized into four progressive phases [22], (Tables 2,3).

Table 2.

Weight training program.

part	Upper body	set × reps	Lower body	set × reps
1-4wk Endurance (12-16RM)	Bench press	4 × 12	Back squat	4 × 12
	Incline chest press	4 × 12	Leg extension	3 × 16
	Barbell Row	3 × 16	Leg curl	3 × 16
	One arm DB row	3 × 16	Hip abduction	3 × 12
	Side lateral raise	3 × 15	DB lunge	3 × 12
5-8wk Hypertrophy (8-12RM)	DB Chest press	4 × 8	Front squat	4 × 10
	Lat pull down	4 × 10	Power Leg press	4 × 8
	Deadlift	3 × 8	DB Goblet squat	3 × 12
	DB Hammer curl	3 × 12	Seated Leg curl	3 × 12
	Triceps push down	3 × 12	Donkey Calf raise	3 × 12
9-12wk Maximum strength (4-8RM)	Push Jerk	2 × 5	BB Squat jump	3 × 5
	Incline DB press	4 × 6	Forward lunge	4 × 8
	Seated row	3 × 8	KB swing	3 × 6
	Shoulder press	3 × 6	Good morning	3 × 5
	SL deadlift	3 × 5	Jump Calf raise	3 × 8
13-16wk power (1-4RM)	Power Clean	2 × 2	Snatch Squat	2 × 3
	Speed Snatch	3 × 3	MB jump Slam	3 × 5
	DB narrow press	2 × 4	KB wide Squat	3 × 5
	DB Kickback	3 × 4	One leg jump	3 × 3
	Push press	3 × 4	Split lunge	3 × 5

Table 3.

Landmine exercise program.

part	Upper body	set × reps
1-4wk	Landmine Squat	3 × 12
	Landmine Shoulder Press	3 × 15
	Landmine Lateral Roll Out	2 × 16
5-8wk	Landmine Smo Squat	3 × 8
	Landmine Kneeling Twist	3 × 12
	Landmine Row	3 × 10
9-12wk	Landmine Squat to Press	3 × 6
	Landmine Swing	3 × 8
	Half Kneeling Rotation press	3 × 4
13-16wk	Landmine Clean & Jerk	3 × 3
	Landmine Split Lunge	3 × 4
	Landmine SL Deadlift	4 × 2

Statistical Analysis

Data processed in this study were analyzed using SPSS version 26.0 (IBM Corp., Armonk, NY, USA). Descriptive statistics were used to calculate the means (M) and standard deviations (SD) for all variables. To examine pre- and post-intervention changes in physical characteristics and fitness-related factors over the 16-week training period, paired t-tests were conducted. Additionally, a repeated two-way analysis of variance (ANOVA) was performed to assess differences between groups and time points. In cases where significant interaction effects between group and time were observed, paired t-tests were conducted for post-hoc comparisons. Statistical significance was set at α = 0.05.

RESULTS

Body Composition

The body composition of female professional volleyball players before and after the 16-week off-season training was compared between the two groups, and the results are presented in. In the WLG, body weight did not show a significant change over time (p = .19); however, significant changes were observed in muscle mass (t = -9.82, p < .001), fat mass (t = 4.06, p = .004), and body fat percentage (t = 4.24, p = .003). In the WG, significant differences over time were found for all variables, including body weight (t = 3.18, p = .013), muscle mass (t = -4.94, p = .001), fat mass (t = 5.85, p < .001), and body fat percentage (t = 5.92, p < .001) (Table 4).

Table 4.

Changes in body composition physical fitness (M ± SD).

	Group	Pre	Post	Paired T-Test			Two-way ANOVA
				T	P		T	P
Weight (kg)	WLG	67.81 ± 8.67	67.20 ± 8.39	1.43	0.19	Time	9.020	0.008**
	WG	68.1 ± 4.17	67.14 ± 4.61	3.18	0.013*	Group	0.001	0.971
						T × G	0.436	0.518
Muscle mass (kg)	WLG	28.78 ± 2.66	30.62 ± 2.87	-9.82	< 0.001***	Time	97.83	< 0.001***
	WG	28.64 ± 2.36	29.86 ± 2.41	-4.94	< 0.001***	Group	0.139	0.715
						T × G	4.20	0.57
Fat mass (kg)	WLG	14.98 ± 4.19	12.90 ± 3.60	4.06	0.004**	Time	47.767	< 0.001***
	WG	16.61 ± 2.98	13.99 ± 2.49	5.85	< 0.001***	Group	0.766	0.394
						T × G	0.641	0.435
BF (%)	WLG	21.80 ± 3.91	18.92 ± 2.99	4.24	0.003**	Time	50.38	< 0.001***
	WG	24.38 ± 4.16	20.82 ± 3.38	5.92	< 0.001***	Group	1.82	0.196
						T × G	0.576	0.459

WLG: weight + Landmine group; WG: weight group; BF: percent body fat;

^*p < .05;

^**p < .01;

^***p < .001.

Physical Performance

The effects of the 16-week linear periodized fitness program were analyzed for time, group, and their interaction, with performance-related variables categorized into strength, power, and muscular endurance. In the WLG, paired t-test analyses revealed significant improvements in all measured variables: DL (t = -2.91, p = .020), BS (t = -3.86, p = .005), CMJ (t = -4.97, p = .001), PU (t = -3.39, p = .009), and SU (t = -4.86, p = .020).

In the WG, significant pre- to post-training improvements were observed in DL (t = -5.33, p = .001), CMJ (t = -3.11, p = .014), PU (t = -3.23, p = .012), and SU (t = -2.89, p = .020). Although BS performance improved post-training (t = -2.17, p = .062), this change did not reach statistical significance.

Two-way ANOVA was conducted to evaluate the interaction effects between time and group. Significant changes over time were observed for DL (p < .001), BS (p < .001), CMJ (p < .001), PU (p < .001), and SU (p < .001). Between-group comparisons indicated no significant differences for DL (F = 0.013, p = .91), BS (F = 2.68, p = .461), PU (F = 0.002, p = .966), or SU (F = 0.171, p = .685); however, CMJ showed a significant between-group difference (F = 12.66, p = .003).

Analysis of the time × group interaction effect indicated no statistically significant interactions for DL (F = 0.615, p = .444), BS (F = 0.571, p = .121), PU (F = 0.098, p = .759), or SU (F = 0.023, p = .880). However, CMJ showed a significant time × group interaction (F = 5.3, p = .035) as well as a significant main effect of group (F = 12.66, p = .035) (Table 5).

Table 5.

Changes in physical fitness (M ± SD).

	Group	Pre	Post	Paired T-Test			Two-way ANOVA
				T	P		T	P
DL	WLG	64.44 ± 15.09	74.44 ± 9.82	-2.91	0.02**	Time	30.15	< 0.001***
	WG	62.22 ± 8.70	75.56 ± 10.14	-5.33	0.001***	Group	0.013	0.91
						T × G	0.615	0.444
BS	WLG	59.78 ± 10.43	68.33 ± 12.19	-3.86	0.005**	Time	19.057	< 0.001***
	WG	58.56 ± 8.00	62.44 ± 10.68	-2.17	0.062	Group	2.68	0.461
						T × G	0.571	0.121
PU	WLG	26 ± 5.36	31.33 ± 4.15	-3.39	0.009**	Time	21.951	< 0.001***
	WG	26.22 ± 6.50	30.89 ± 7.04	-3.23	0.012*	Group	0.002	0.966
						T × G	0.098	0.759
CMJ	WLG	46.66 ± 5.55	54.22 ± 2.05	-4.97	0.001***	Time	33.05	< 0.001***
	WG	45.22 ± 1.36	47 ± 1.64	-3.11	0.014*	Group	12.66	0.003*
						T × G	5.3	0.035*
SU	WLG	40.89 ± 6.45	44.33 ± 5.96	-4.86	0.02*	Time	23.918	< 0.001***
	WG	42.11 ± 6.77	45.77 ± 8.61	-2.89	0.02*	Group	0.171	0.685
						T × G	0.023	0.88

WLG: weight + Landmine group; WG: weight group; DL: dead lift; BS: back squat; PU: push up; CMJ: countermove jump; SU: sit up;

^*p < .05;

^**p < .01;

^***p < .001.

DISCUSSION

The present study was designed to investigate the effects of a traditional linear periodized strength training program, supplemented with barbell-based landmine exercises, on the physical performance of professional volleyball players. To achieve this objective, an experimental study was conducted, and the results of the paired t-test revealed significant improvements across all measured variables in both groups, confirming that both training approaches were effective in enhancing physical performance. However, the two-way ANOVA conducted to examine the interaction effects between group and time revealed a significant interaction only for CMJ (countermovement jump). Specifically, the group that combined landmine exercises with linear periodized training demonstrated a greater improvement in CMJ performance compared with the group that performed linear periodized training alone. Based on these findings, the present study aims to discussion the practical applicability and potential implementation strategies of landmine exercises, particularly in relation to their effectiveness in enhancing explosive power performance.

The significant improvements observed in overall physical performance indicators in both groups following the intervention are consistent with previous studies that have demonstrated the strength-enhancing effects of the linear periodization model [15,23,24] Linear periodized training induces neuromuscular adaptations through the systematic manipulation of intensity, repetitions, and sets based on the principle of progressive overload. Moreover, it offers the advantage of maintaining high training stimuli while minimizing injury risk over the course of a long competitive season. Supporting this perspective, Evans [25], in a comprehensive review on periodized training, reported that planned and structured periodization programs are more effective in improving strength compared with non-periodized training. Taken together, these findings suggest that systematically designed linear periodization programs should be considered a key strategy for enhancing athletic performance in volleyball players during the off-season.

In contrast, the between-group difference observed in CMJ performance is noteworthy. Stone et al. [26] reported that incorporating multi-joint and multi-planar movements is effective for improving explosive strength, while Newton & Kraemer [27] emphasized that greater similarity between training tasks and sport-specific movements enhances the transfer of training effects. Accordingly, the greater improvement in jump performance observed in the group that incorporated landmine exercises may be interpreted as a reflection of this principle of specificity. Cormie et al. [28], in their physiological and neuromuscular analysis of explosive power production, argued that improvements in jump performance are not solely attributed to increases in maximal strength, but are also closely associated with enhanced neuromuscular efficiency, including faster muscle fiber conduction velocity (MFCV) and greater motor unit recruitment. Given its unique ability to generate vertical, horizontal, and rotational forces while minimizing instability, the landmine exercise may have effectively facilitated these neuromuscular adaptations, thereby contributing to the superior improvements in jump performance observed in this study.

From another perspective, the superior improvements in jump performance may also be attributed to the biomechanical similarity between landmine exercises and the vertical jump. Movements such as the landmine squat, split jerk, and lunge rotational press require explosive extension of the hip, knee, and ankle joints the three primary lower-limb joints closely mirroring the movement patterns involved in volleyball actions such as spiking and blocking. This kinematic resemblance is likely to have amplified the transfer effects of training, thereby contributing to the greater improvements in jump performance observed in the landmine group. Furthermore, a key aspect of jump performance is the effective transfer of ground reaction force (GRF) from the lower to the upper body without loss. The landmine exercise, which involves loading around a fixed axis, minimizes unnecessary horizontal displacement while maximizing vertical force production, thereby potentially facilitating improvements in CMJ performance. Additionally, landmine movements incorporate rotational and anti-rotational components, which enhance core stability by engaging the abdominal and spinal musculature. This improved core stability likely promotes the efficient transfer of force generated in the lower limbs to the upper body, contributing to the observed gains in vertical jump performance.

In volleyball, spiking and blocking are key determinants of performance, and improvements in jump performance are likely to translate directly into enhanced competitive outcomes. Therefore, from a practical standpoint, incorporating a proportion of landmine-based, full-body explosive exercises into training programs during both the in-season and off-season periods may represent an effective strategy for enhancing athletic performance.

However, a notable limitation of this study is that the WLG completed the landmine program in addition to the base resistance-training program, resulting in a greater overall weekly training volume compared with the WG. Therefore, the superior improvements observed in the WLG—particularly in CMJ—cannot be attributed solely to landmine-specific mechanical characteristics. Differences in total workload, accumulated neuromuscular stimulus, or learning effects may also have contributed. Future studies should incorporate an equal-volume comparator group to isolate modality-specific adaptations and more precisely determine the unique contribution of landmine exercises.

In addition, the study sample consisted of only 18 professional female volleyball players, which limits the generalizability of the findings. Professional athletes typically possess highly developed physical and technical capacities, and their responsiveness to training stimuli may differ from that of amateur, collegiate, or youth athletes. Moreover, real-world factors such as competitive schedules, individual fatigue, and injury status during the intervention period may have influenced the results.

In summary, the present study highlights the importance of a systematic linear periodized strength-training program for enhancing physical performance in professional volleyball players, and suggests that incorporating barbell-based landmine exercises may offer additional benefits. However, these findings should be interpreted with caution given the increased training volume in the WLG and the restricted sample characteristics. Future research employing volume-matched designs and broader athlete populations is needed to clarify whether landmine exercises elicit unique modality-specific adaptations or whether their benefits are primarily attributable to increased overall training stimulus.