Allyson G. Box

High-intensity exercise has been shown to result in physiological benefits. However, little is known about why individuals choose to initiate and continue engaging in this type of exercise. It is likely individual differences exist that explain why some maintain a high-intensity exercise regimen while others do not. Thus, the purpose of the present study was to examine the predictive role of intensity preference and tolerance traits on performance and enjoyment from a high-intensity workout. Participants (N  = 34; 33 ± 8 yrs) completed the Preference for and Tolerance of the Intensity of Exercise Questionnaire, then performed a 12-minute high-intensity workout (HIW; consisting of a 5 pull-ups, 10 box jumps, & 15 wall ball throws AMRAP). Intensity preference [b(lower – upper CI); 0.475(0.169–0.782), P = 0.002], but not tolerance [0.140(−0.254–0.535), P = 0.486], explained variance in HIW performance (i.e., number of repetitions completed in the 12-min AMRAP), while neither preference nor tolerance were meaningfully associated with post-HIW enjoyment (r_s < 0.27). However, performance explained meaningful variance in enjoyment [0.435(0.233–0.637.18), P < 0.001]. Thus, intensity-preference influences the number of repetition completed during a HIW, but intensity-preference and tolerance are less important for HIW enjoyment. Rather, more completed repetitions was related to greater enjoyment, and experiencing greater exercise enjoyment may lead to continued high-intensity exercise engagement.

Background: Firefighting is a strenuous profession requiring adequate levels of fitness for effective job performance. Providing firefighters with a safe and effective fitness program is essential for optimal performance. The purpose of this project was to examine changes in various parameters of physical fitness and firefighter ability following a 7-week high intensity functional training (HIFT) program. Methods: Participants were male firefighter recruits (N = 89; age = 27.1 ± 4.2 years, height = 1.78 ± 0.1 m, BMI = 28.1 ± 4.2) enrolled in a Basic Operations Firefighter Academy. Fitness and firefighting ability (via the Academy Firefighter Challenge) were assessed at Weeks 1 and 7 of the Academy. Results: Significant improvements in both fitness and firefighter ability were seen following the HIFT program. Specifically, fitness (BMI, cardiovascular fitness, muscular endurance) improved significantly [Hotelling’s T² = 8.98, F(5, 84) = 150.92, p < 0.001, η²_p = 0.90]. Firefighter ability also improved significantly [Hotelling’s T² = 3.95, F(7, 88) = 46.26, p < 0.001, η²_p = 0.80]. Conclusions: Following a 7-week Basic Operations Firefighter Academy that included daily HIFT, significant increases in fitness and firefighting ability were observed. These findings suggest that HIFT appears to be an effective means of improving fitness and firefighting ability in recruit firefighters.

Background: Regular exercise in firefighters may be effective in preventing or attenuating ill health (e.g., hypertension, diabetes, and obesity), as well as improving their firefighting ability. The purpose of this study was to investigate the relationship between physical fitness and firefighting ability. Methods: Male firefighter recruits’ (n = 89; age = 27.1 ± 4.2 yrs) physical fitness and firefighting ability were assessed at Week 1 and Week 7 during a basic firefighting training academy. Physical fitness was assessed via 1.5 mile run time, sit-up and push-up repetitions, the Young Men’s Christian Association (YMCA) bench press test, vertical jump height, and sit-and-reach flexibility, while firefighting ability was assessed via completion time on a firefighting skills test. Results: Fitness predicted significant variance in firefighting ability at Week 1 (R²= 0.46; p < 0.01) and Week 7 (R² = 0.46; p < 0.01), after accounting for age and body mass index. Cardiovascular endurance accounted for 22.4% (FΔ (1, 85) = 25.75) and 39.3% (FΔ (1, 85) = 55.53) while muscular endurance accounted for an additional 19.0% (FΔ (3, 82) = 10.34) and 6.3% (FΔ (3, 82) = 3.2) unique variance in firefighting ability at Week 1 and Week 7, respectively. Conclusions: Given the strong association between fitness and firefighting performance, municipal departments may want to focus on increasing fitness levels among firefighters.

High-Intensity Interval Exercise: Methodological Considerations for Behavior Promotion From an Affective Perspective

There is a lack of understanding as to how exercise motives differ across age cohorts. Over the last decade, CrossFit training (CFT) has emerged as a forerunner in the fitness industry, which seems to appeal to a large number of individuals. Thus, the purpose of this study was to examine participatory motives among individuals of different age cohorts who engage in CFT. Methods: 735 adults (32.4 ± 8.1 years; 53.1% male) with at least 3-months of CF experience completed an online version of the Exercise Motivation Inventory (EMI-2) survey. Participants were divided into four age-cohorts: College age (n = 123), Young adult (n = 291), Middle age (n = 288), and Older adult (n = 33). Results: Significant differences were found between age cohorts and participatory motives (F_s(3, 731) = 3.29–22.42, p_s< .03, η² p = .012–.084). Overall, older participants scored higher on health-related motives, while younger participants scored higher on social motives relative to their counterparts. Conclusions: This study provides a first look into motives for CFT across different age cohorts. Encouragement of exercise programmes that support relevant motives for different age groups could be more effective for exercise adherence and promotion of long-term health benefits.

Background: Specific mood states were examined during the CrossFit Open, a consecutive 5-week fitness competition involving five separate CrossFit^® workouts, to determine whether the unique design or strenuous workouts of the competition resulted in acute and/or chronic mood state alterations. Methods: Participants (n = 8) completed the Profile of Mood States (POMS) questionnaire one-week prior to the competition (baseline), prior to (PRE), immediately post (IP), 30-min post- (30P) and 60-min post-workout (60P) each week. Tension, depression, anger, confusion, fatigue and vigor were derived from the POMS, as was Total Mood Disturbance (TMD) and an Energy Index (EI). Results: Workout intensity exceeded 93% HR_max each week. No differences were observed between baseline and PRE-workout mood states across weeks, indicating little effect of the unique competition design. Significant (week x time) interactions were observed for TMD (p = 0.037), EI (p = 0.038) and fatigue (p = 0.005). Acute mood state fluctuations were consistent across each week, where mood states improved to and beyond PRE values 60-min post-workout. Conclusions: In competitors, the differences in workout design between each week did not influence mood states. This may be related to adaptation to this style of training, while the acute mood state alterations are likely due to the workout intensity.

To determine the salivary steroid response to high-intensity functional training (HIFT) competition workouts, saliva samples were collected from ten recreationally trained male and female competitors during a 5-week (WK1–WK5) international competition. Competitors arrived at their local affiliate and provided samples prior to (PRE) their warm-up, immediately (IP), 30-min (30P), and 60-min (60P) post-exercise. Samples were analyzed for concentrations of testosterone (T), cortisol (C), and their ratio (TC). Generalized linear mixed models with repeated measures revealed significant main effects for time (p < 0.001) for T, C, and TC. Compared to PRE-concentrations, elevated (p < 0.05) T was observed at IP on WK2–WK5 (mean difference: 135–511 pg·mL⁻¹), at 30P on WK3 (mean difference: 81.0 ± 30.1 pg·mL⁻¹) and WK5 (mean difference: 56.6 ± 22.7 pg·mL⁻¹), and at 60P on WK3 (mean difference: 73.5 ± 29.7 pg·mL⁻¹) and WK5 (mean difference: 74.3 ± 28.4 pg·mL⁻¹). Compared to PRE-concentrations, elevated (p < 0.05) C was noted on all weeks at IP (mean difference: 9.3–15.9 ng·mL⁻¹) and 30P (mean difference: 6.0–19.9 ng·mL⁻¹); significant (p < 0.006) elevations were noted at 60P on WK1 (mean difference: 9.1 ± 3.0 ng·mL⁻¹) and WK5 (mean difference: 12.8 ± 2.9 ng·mL⁻¹). Additionally, TC was significantly reduced from PRE-values by 61% on WK1 at 60P (p = 0.040) and by 80% on WK5 at 30P (p = 0.023). Differences in T, C, and TC were also observed between weeks at specific time points. Although each workout affected concentrations in T, C, and/or the TC ratio, changes appeared to be modulated by the presence of overload and workout duration. During periods of elevated training or competition, athletes and coaches may consider monitoring these hormones for consistency and as a means of assessing workout difficulty.