Romanova D.A., Loginov S.I. Morphophysiology of middle-aged men playing ice hockey

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Publication date: 15.06.2024
DOI: 10.24412/2782-6570-2024_03_02_3
UDC 616; 534.292

MORPHOPHYSIOLOGY OF MIDDLE-AGED MEN PLAYING ICE HOCKEY

D.A. Romanova, S.I. Loginov

Vladimir State University named after A.G. and N.G. Stoletovs, Vladimir, Russia

Abstract. The aim was to assess the level and structure of physical activity, as well as morphophysiological indices reflecting the fitness for aerobic and anaerobic physical activity in men aged 45-59 years old and involved in ice hockey. The sizes and volumes of the left and right ventricles of the heart and the maximum oxygen uptake of the hockey players were significantly higher than those of the non-hockey players and were within the age norm. Blood glucose and lactate increased to a greater extent in non-hockey players (p<0.05). No signs of cardiac hypertrophy were detected. Hockey players have greater muscle mass, bone mineral mass, water and basal metabolic rate compared to non-hockey players, who have a higher percentage of total and visceral fat (p<0.05). The duration of moderate- and high-intensity physical activity was significantly higher in hockey players, whereas the duration of sedentary activity, on the contrary, was significantly higher in non-hockey players (2612±443 versus 746±245 minutes per week, p<0.001). Playing ice hockey at the amateur level (with appropriate supervision) can be recommended as an effective way to introduce middle-aged men to regular physical activity.

Keywords: echocardiography, body composition, glucose and lactate concentrations, physical activity, middle-aged men, ice hockey.

Introduction. One of the most important issues of physiology is the study of the mechanisms of immediate and long-term adaptation of a human body to physical activity in sports [1]. In order to achieve a favorable adaptive result of regular sports activity, a special functional system occurs in an athlete’s body, aimed at increasing activity of aerobic and anaerobic energy systems, including cardiorespiratory and musculoskeletal system with the participation of central, autonomic nervous system and increased activity of pituitary-hypothalamic and neurosecretory system [2]. The result of the work of such a system depends primarily on the functional state of the heart and its ability to increase the value of cardiac output with increasing loads especially in middle-aged people [3].

The morphophysiological description of ice hockey players was presented almost half a century ago [4-6], however, due to its dynamicity this game still gains interest of physiologists and sports physicians [7-8]. Ice hockey is a high-intensity team sport that requires not only well-honed skating and strength techniques, but also explosive muscular efforts in leg work during acceleration and direction changes, and in hand work when shooting [9]. Therefore, for effective in-game actions players must have sufficient physical fitness, which would include a high level of muscle strength development [10], as well-developed metabolic pathways of obtaining energy – glycolytic (anaerobic pathway) [11] and oxidative phosphorylation (aerobic pathway) [12]. Currently, the physiological and physical profiles of professional players have been well studied [8]. However, the problem is that most of the work on the morphology and physiology of ice hockey is devoted to the study of young individuals, while middle age remains understudied. There are very few middle-aged players in professional hockey, but in amateur hockey, more than half a million men and 70 000 women play so-called gentlemen's hockey in Canada alone. In Russia, about 25 000 men regularly play in the Night Hockey League, which requires scientific-methodological and biomedical support, taking into account the peculiarities of middle age.  

Middle or mature age is a transitional age period of a person from youth to old age. It is divided into two periods: the first: mature age of men – 21-35 years, women – 20-35 years and the second: men – 35-60 years, women – 35-55 years [13]. Currently, in accordance with the new WHO classification [14], the young age has been extended to 44 years, which accordingly changed the boundaries of the second period of mature age for men, i.e. 45-59(60) years.

Therefore the aim of our study was to estimate morphophysiological indices reflecting the fitness for aerobic and anaerobic physical activity in men aged 45-59 years old and involved in ice hockey. In addition, our data may go some way to answering the question of whether middle-aged men should try ice hockey for health reasons, and whether ice hockey can be recommended as a way to encourage middle-aged men to engage in regular physical activity.

Methods and organization. Practically healthy men aged 45-59 years, who played ice hockey three times a week at the Kovrov Ice Palace (Vladimir Oblast) from 8:45 to 10:15 pm (experiment group, EG, n=30) participated in the study (fig. 1).

Fig. 1. The “Bagration” team, Kovrov – the winner of the VIII final of the United Amateur Hockey League, Sochi 2023

The control group (CG) included peers (n=30) who did not play hockey. We measured body length (BL, m) and body mass (BM, kg) using commonly accepted methods. Body composition was measured with the bioimpedance method using the ВС-730 Tanita analyzer (Japan). We defined muscle mass (MM, kg), bone mass (BM, kg), fat mass (FM, kg), visceral fat mass (VFM, c.u.), water content (W, kg) and basal metabolic rate according to the Harris-Benedict calculator (BMR, kcal). BMI was calculated as BM/BL² (kg/m²).

Resting cardiac function indices were examined by transthoracic echocardiography on a Sonoscape s40exp ultrasound device. Measurements of heart chamber size and volume, ventricular wall thickness were performed according to recommendations [15]. To assess performance, we used the PWC170 bicycle ergometer test, glucose and lactate concentrations were determined in finger blood before and after the test using the BM-Lactate portable express system.

To assess level and structure of physical activity (PA) among players and non-players, we applied the Russian version of IPAQ (International Physical Activity Questionnaire) [16]. It allowed collecting data on the time and amount of energy spend on of low-, moderate- and high-intensity PA according to four sections: work, travel (commuting), home chores, and leisure. In each section, participants were required to report PA frequency for the last 7 days (number of days) and its duration (hours and minutes). The initial data were processed according to the standard protocol of the IPAQ standard version [17] using special software [16]. The number of daily steps per week was determined using the Tanita AM-120 pedometer (Japan).

Descriptive statistics were performed using Statistica 12 (StatSoft, USA). We calculated the arithmetic mean (X̅) and standard deviation (SD). The Kolgomorov-Smirnov test was used to check on the distribution normality. In case of normal distribution, we applied the Student’s t-test for independent samples when p≤0,05.

Results and discussion. Studies conducted have shown no differences in overall dimensions and age between ice hockey players and non-players. At the same time, hockey players have greater muscle mass, bone mineral mass, water mass and basal metabolic rate compared with non-hockey players, who are characterized by a greater percentage of total and visceral fat (p<0.05) (table 1).

Our echocardiographic study showed that the end-diastolic and end-systolic dimensions and volumes of the left ventricle of the heart were significantly higher in ice hockey players compared with those of their non-players. Stroke volume, right heart parameters, and resting HR were also higher in hockey players, whereas the value of ejection fraction was higher in non-players (table 2).

Table 1

Body dimensions and composition indices in ice hockey players and non-players, X̅±SD

Indices	Hockey players, n=30	Non-players, n=30	P
Age, years	49.7±5.26	52.1±5.31	0.0839
Body length, cm	178.3±5.49	177.4±5.03	0.5106
Body mass, kg	85.9±9.08	87.6±9.02	0.9654
Body mass index, kg/m2	26.7±2.39	28.2±3.64	0.0642
Muscle mass, kg	61.6±5.02	55.8±6.87	0.0004
Bone mass, kg	3.35±0.33	3.78±0.72	0.0001
Fat mass, %	23.9±2.99	26.9±4.69	0.0045
Visceral fat, %	8.9±1.14	11.0±3.18	0.0012
Water, kg	53.3±4.54	48.1±5.63	0.0002
Basal metabolic rate, kcal	1897.8±149.75	1789.8±122.63	0.0034

Note: the level of significance was calculated using the Student's t-test for unrelated groups at a significance level of p≤0.05

Table 2

Main echocardiographic indices of ice hockey players and non-players, X̅±SD

Indices	Hockey players, n=30	Non-players, n=30	P
Left atrial size, mm	27.6±6.71	27.5±6.71	NS
LVEDD, mm	36.4±6.79	29.1±6.04	0.0001
LVESD, mm	30.7±5.45	36.7±5.21	0.0001
Left ventricle, EDV, ml	88.9±14.44	79.0±13.35	0.0076
Left ventricle, ESV, ml	48.4±15.33	28.6±0.64	0.0001
Right atrial size, m	32.9±4.98	30.2±4.47	0.0312
Right ventricular size, mm	28.5±4.27	22.2±4.84	0.0001
LV wall thickness, mm	8.89±1.88	8.1±1.51	0.0780
RV wall thickness, mm	4.1±0.63	3.6±0.55	0.0018
VS thickness, mm	10.9±2.32	10.1±3.32	0.2838
Stroke volume, ml	69.0±12.41	60.8±15.53	0.0274
Cardiac output, l	3.64±0.45	3.46±0.57	0.1799
Ejection fraction, ml	60.1±5.47	63.4±6.63	0.0536
Resting HR, beats/min	63.5±7.12	68.6±6.03	0.0042

Note: LVEDD – left ventricular end-diastolic diameter; LVESD – left ventricular end-systolic diameter; EDV – end-diastolic volume; ESV – end-systolic volume; LV – left ventricle; RV – right ventricle; VS – ventricular septum; HR – heart rate

The values of maximum oxygen uptake (VO₂ max) and HR before and after the bicycle ergometer test were significantly higher in hockey players than in non-players (fig. 2, A). Glucose concentration before the test was higher in non-players, whereas there were no differences in lactate. After the test, blood glucose and lactate increased in both non-players and players, but to a greater extent in the players (fig. 2, B).

The level of PA at work, during leisure time and in general is significantly higher in hockey players than in those who lead a normal lifestyle and occasionally exercise. PA spent for commuting by car or other means of transport did not differ between the two samples (table 3).

Fig. 2. Changes in maximum oxygen uptake (VO₂ max) and heart rate (HR) (A), and changes in blood glucose and lactate (B) before and after the bicycle ergometer test in hockey players and non-players. М±0.95 confidence interval

Table 3

Indices of physical activity and sedentary behavior of individuals, who play and do not play ice hockey, X̅±SD

Indices	Players, n=30	Non-players, n=30	P
Work, min/week	1012±384	661±209	0.0001
Commuting, min/week	992±631	119±149	0.0001
Time spent at home and summer cottage, min/week	228±205	257±209	0.5895
Leisure, min/week	948±241	124±80	0.0001
Total PA, min/week	2444±500	1161±359	0.0001
Time spent sitting (working days), min	495±182	1940±449	0.0001
Time spent sitting (weekend), min	253±109	672±199	0.0001
Time spent sitting (total), min	746±245	2612±443	0.0001

Note: PA – physical activity; the level of significance was calculated using the Student's t-test for unrelated groups

The duration of the moderate-intensity physical activity (MIPA) is significantly higher in ice hockey players compared to non-players (786±289 vs 316±232 minutes per week, p<0.0001) (fig. 3).

High-intensity physical activity (HIPA) was also statistically higher in players than in non-players (548±237 vs. 123±65 minutes per week, p<0.0001), which, when combined with MIPA, is even higher than the recommended 150 minutes per week [14].

Leisure-time physical activity in non-players was lower than the recommended norm and amounted to 124±80 minutes per week, which is 7.6 times less than in hockey players (table 3). The same was true for walking time (1118±212 vs. 822±252 minutes per week, p<0.001 in favor of hockey players).

Fig. 3. Duration of the moderate-intensity physical activity (MIPA), high-intensity physical activity (HIPA), time spent walking, sitting and sleeping for participants, who play ice hockey, (hockey players, n=30) and non-players (non-players, n=30), min/week

Note: vertical lines show the value of standard deviation; * – differences are reliable at significance level p<0.05

In contrast, the duration of sedentary time was significantly higher in non-players compared to hockey players (2612±443 vs 746±245 minutes per week, p<0.001): 6.2 hours/day for non-players vs 1.8 hours/day for hockey players. It can be assumed that a higher level of sports activity allows those, who play ice hockey regularly, to maintain high levels of daily physical activity and significantly reduce sedentary time. This reflects the importance of physical activity in promoting health and points to the need to encourage people to exercise regularly.

Exercise is known to be associated with a number of morphophysiological cardiac adaptation processes [18] (fig. 4).

Fig. 4. Multifactorial nature of morphological and functional changes in the heart of athletes [18]

These functional manifestations, referred to as the “athletic heart”, may include increased left and right heart cavity size, increased wall thickness of the left ventricle (LV) and increased indices of systolic and diastolic function at rest and during exercise compared to those who do not exercise [19]. The “athletic heart” phenomenon involves adaptation of the whole heart, it is not limited by one chamber or function, therefore it is necessary to evaluate all cardiac chambers in the remodeling under the effect of physical activity. Structural, functional, spatial and geometric changes occur under the influence of training, with ventricular chamber sizes and left ventricular mass increasing significantly in athletes compared to the control group. Thus, intense ice hockey training is associated with typical myocardial adaptation [18]. Older athletes have higher LV mass and ventricular volumes compared to the control group of the same age, who lead a sedentary lifestyle, without evidence of LV dysfunction [20].

In our study, hockey players aged 45-59 years also had larger cardiac chamber sizes and volumes compared to the control group, but their values did not exceed the age norm. Thus, LVESD and LVEDD in the hockey players were  36.4±6.79 and 30.7±5.45 mm with a norm of 50.2±4.1 (ranks 42.0-58.4 mm) and 32.4±3.7 (ranks 25.0-39.8 mm) respectively. ESV and EDV in our samples were 88.9±14.4 and 48.4±15.3 ml with a norm of 106±22 (ranks 62-150 ml) and 41±10 (ranks 21-61 ml) respectively. The ejection fraction was higher in the control group and amounted to 63.4±6.68 vs 60.1±5.47 ml in the hockey players (p=0.0536). Thickness of the ventricular septum (VS) did was not different between the subjects of both groups. VO₂ max and HR significantly increased after the bicycle ergometer test with with a predominant increase in HR in non-players, indicating an insufficient efficiency of cardiac work regulation by HR rather than by increasing SV (fig. 2, A).

Blood glucose was higher in non-players before and after the test, but lactate did not differ between groups before the test (fig. 2, B). After the test, blood lactate increased from 1.39±0.87 to 9.68±2.63 mmol/l in hockey players, and from 1.96±0.9 to 12.42±3.38 mmol/l in non-players, i.e. more than 6-fold in both groups. At the professional level, blood lactate in ice hockey players during a game varies from 8.7 to 15.1 mmol/l [4]. The rest between changes lasts 3-5 minutes, but the high intensity of work during the change dictates the use of short changes, which helps to reduce lactate accumulation in the blood and muscles. A recovery period is necessary for a partial (up to 60-65%) phosphocreatine resynthesis and restoration of ATP reserves. Obviously, in our case, for amateur players, most of the work on ice is done in the aerobic mode, as evidenced by the moderate increase in VO₂ max. However, the six-fold increase in blood lactate in the conditions of the model experiment on the bicycle ergometer suggests the possibility of the glycolytic process activation and confirms the anaerobic nature of the game.

Professional hockey players are meso-morphic and not overweight. According to the data from [15], the BMI of middle-aged hockey players (42.7±6.9 years) is 28.4±4.4 kg/m². Our data is similar – 26.7±0.44 kg/m² in hockey players and 28.2±0.67 kg/m² in non-players. The fat content in hockey players is higher than the data received in previous studies and amounts to 23.9±2.99% compared to elite young hockey players (17.2±3.17%) [21]. The resting HR in our sample was slightly higher than the HR in the Canadian sample – 63.5±7.17 vs 59±9 beats/min, and after the next change – 154±4.5 beats/min.

In Canada, more than 500 thousand men play amateur hockey, but the safety of this activity, as well as in our country, is insufficiently studied. High-intensity training is associated with a risk of cardiac abnormalities. All participants had a maximum heart rate (HRmax) of 184±11 beats/min during the game, which is above the target HR for exercise, calculated as 55-85% of the age-predicted HRmax. The average time, during which the HR exceeded 85% of the age-predicted HRmax, was 30±13 munites. Unstable ventricular tachycardia and ST-segment depression of unknown etiology were observed in 70% [10].

More than 25 thousand middle-aged men play in the Night Hockey League, and the health problems are the same as in Canada. Nevertheless, under our conditions we consider ice hockey (with proper control) as an effective way to introduce middle-aged men to regular physical activity.

Health experts are concerned with the physical activity of middle-aged men. According to the questionnaire conducted by the All-Russian Research Institute of Physical Culture and Sports, Russian men at the age of 40-49 years take 7887±2955 steps per day and are moderately active, while at the age of 55-59 years men take only 6207±2157 steps per day, which is considered as low physical activity. Normal values are 7000-8000 steps per day [22]. In our sample those, who play hockey, take 9750.3±3145.4 steps per day, while those, who don’t play, take 7803.6±3145.2 steps per day, which is less compared to hockey players (p=0.0261). These data suggest that the former have a physical activity level above the national average for their age group, while the latter are content to be within their age group and moderately active.

Let’s look at some of the arguments for and against ice hockey as a stimulus for physical activity.

The “for” arguments include the following:
1) playing hockey promotes increased physical development and game thinking, which ultimately increases player competence;
2) players assert that practice and games are especially important to them, since they provide the joy of fighting on the ice, the pleasure of passing and scoring the puck, and the enhancement of the male “ego”;
3) players communicate with each other during practice and after the game in the locker room to discuss the results, analyze mistakes and shortcomings in practice with the coach, outline plans for the future. They agree on activities outside training, both as a team and as friends (e.g. trips to the countryside, attending matches of the masters' team, concerts, etc.).

Therefore, the need for competence, independence and communication creates and strengthens the internal motivation for physical activity and encourage these men to go to practice and play hockey late at night after a day of work.

Arguments “against” include:
1) risk of injury;
2) the high cost of renting ice and purchasing equipment;
3) late hours for practice.

Note that middle-aged men are a hard-to-reach population in any country, and it is difficult to attract them to regular physical activity by trivializing healthy lifestyles. Using ice hockey as an example, gendered notions of strength, independence and courage can be convincingly demonstrated to men, which are key to engaging middle-aged men in regular physical activity.

Conclusion. Three times a week, 4.5 hours of evening training contributes to an increase in the size and volume of cardiac chambers in ice hockey players compared to non-players. At the same time, the changes in size do not exceed the age norm. Hypertrophy of myocardium of the left ventricle and right heart sections was not found, which indicates the adequacy of physical loads. The degree of athletic adaptation in our case does not exceed normal limits of the heart’s size and function. This allows us to recommend ice hockey for healthy middle-aged men and to positively answer the question posed at the beginning of the article that this sport, due to its attractiveness, can be considered as a means of attracting middle-aged men to regular physical activity.

Ice hockey training not only contributes to a positive restructuring of body composition, as manifested by greater muscle mass, bone mineral content, water and basal metabolic rate, which have a higher percentage of total and visceral fat (p<0.05), but also to an increase in daily physical activity and a decrease in the duration of sedentary behavior compared to non-hockey players. Ice hockey training also contributes to the development of intrinsic motivation based on basic needs for competence, independence and communication based on ideas about masculine ideals.

Conflict of interest. The authors declare no conflict of interest.

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INFORMATION ABOUT THE AUTHORS:
Dina A. Romanova – Post-Graduate Student, Vladimir State University named after A.G. and N.G. Stoletovs, Vladimir, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..
Sergej I. Loginov – Professor, Vladimir State University named after A.G. and N.G. Stoletovs, Vladimir, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it..

For citation: Romanova D.A., Loginov S.I. Morphophysiology of middle-aged men playing ice hockey. Russian Journal of Sports Science: Medicine, Physiology, Training, 2024, vol. 3, no. 2. DOI: 10.24412/2782-6570-2024_03_02_3