Table 12 Changes of haematological variables related to acute exercises in various environmental conditions

Acute exercise in normal ambient conditions

Morici et al. [83]

Rowers (n = 20)

After warmup, athletes underwent 10 min of full rest during which the rowing equipment was mounted and checked. Data were collected at least 24 h after a training session (rest) and shortly after all-out rowing over 1000 m

= (NS)

↑ + 25% (10 min)

–

↑ + 7% (10 min)

↓ − 7% (10 min)

Lobigs, Sottas et al. [7]

Endurance athletes (n = 33)

Subjects performed an exercise cycle ergometer challenge designed to promote an acute, maximal shift in PV: 30 min maximal step‐test on a cycle ergometer (5 min steps of 25–50 W increments)

↑ (30 min)

–

↑ (30 min)

–

↓ − 17% (30 min)

Kuipers et al. [84]

Speed skaters (n = 277)

Haematological parameters were analysed in blood samples taken pre-competition (T1) and post-competition (T2) in elite male and female speed skaters participating in long-track ISU speed skating events

↓ − 5% (T2)

= (NS)

–

–

–

Robinson et al. [85]

Recreational athletes (n = 25)

Blood samples were collected before and after a controlled cycle ergometer exercise. Exercise was as follows: 15 min of warmup, then 30 min at a constant power of 70% of the maximal aerobic power and finally 15 min at maximal effort (T1). The subjects were allowed to drink water as needed

↑ + 6% (T2)

= (NS)

–

↑ + 8% (T2)

↓ − 11% (T2)

Miller, Teramoto et al. [86]

Endurance athletes (n = 12)

Twelve subjects underwent multiple controlled exercise trials designed to induce varying levels of PV shifts: 75%, 65% and 55% power output of their determined VO_2peak

↑ (10 min)

↑ (10 min)

↑ (10 min)

↑ (10 min)

↓ − 7% (10 min)

Acute exercise in hot conditions

Diaz et al. [87]

Recreational athletes (n = 5)

Each subject participated in six separate tests consisting of 45 min of rest followed by 45 min of submaximal work on a cycle ergometer at 50 °C. They worked at approximately 30% (E1) and 45% (E2). VO_2max was measured in each of the following postures: upright (UR), low sit (LS) and supine (SU)

↑ + 16% ↑ + 11% ↑ + 10% (E2)

–

–

↑ + 12% ↑ + 7% ↑ + 7% (E2)

↓ − 20% ↓ − 16% ↓ − 13% (E2)

Kenefick et al. [88]

Recreational athletes (n = 32)

Thirty-two men divided into two cohorts—euhydration (E) and hypohydration (H)—completed trials in: ambient temperature (T1), 10 °C (T2), 20 °C (T3), 30 °C (T4) and 40 °C (T5). 30 min of cycle ergometry (at 50% VO_2max) was performed

↑/↑ (T5)

–

–

↑/↑ (T5)

↓ − 11%

↓ − 15% (T5)

Myhre and Robinson [89]

Recreational athletes (n = 12)

Twelve unacclimatized men rested for 4 h in a hot environment (50 °C) with or without fluid replacement

↑ + 2% (4 h)

–

–

↑ + 6% (4 h)

↓ − 8% (4 h)

Jimenez et al. [90]

Recreational athletes (n = 8)

In the thermal dehydration experiment, the subjects were dehydrated for approximately 2 h by passive controlled hyperthermia in a semi-recumbent posture. For each trial, the protocol comprised three phases: a 90-min period in a thermoneutral environment (T1), a period in which subjects were exposed to a variation in body hydration (T2) and a second 90-min period in a thermoneutral environment (T3)

↑ (T2)

–

–

↑ (T2)

↓ − 12% (T2)

Acute exercise in cold conditions

Vogelaere et al. [91]

Recreational athletes (n = 25)

Subjects began with a 30-min rest period (T1). Next, they performed either a cycle ergometer test during which they performed a 120-min sub-maximal exercise corresponding to 40% of the maximal power (SUB) or a progressively increasing workload till exhaustion characterised by an initial 60 W work (T2). Finally, subjects experienced 30 min of passive recuperation (T3)

↑ + 5% ↑ + 9% (T2)

–

–

↑ + 8% ↑ + 8% (T2)

↓ − 7% ↓ − 6% (T2)

Vogelaere et al. [92]

Recreational athletes (n = 6)

In a study of six young males, the experimental group, resting in a dorsal reclining position, was exposed successively to a thermoneutral environment (30 min, T1), a cold environment (1 °C; 30 min, T2), and a 60-min recovery period in thermoneutral conditions while the control group, also resting in a dorsal reclining position, was exposed to thermoneutrality (control, T3) for the entire 120 min

↑ + 4% (T2)

–

–

–

↓ − 15% (T2)

Acute exercise in hypoxic conditions

Siebenmann et al. [93]

Recreational athletes (n = 9)

Nine healthy, normally trained, sea-level residents (eight men, one woman) sojourned for 28 d at 3454 m. They remained at that altitude for 4 weeks. Individual physical activity was maintained by hiking/mountaineering, ergometer cycling and resistance training

↑ (4 weeks)

↑ + 117% (9 d) *Ret count

↓ (4 weeks)

↑ (4 weeks)

↓ − 11% (4 d)