PainSci summary of Schipke 2001: ?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided at the bottom of the page, as often as possible.
Heart rate variability (HRV) refers to the slight wobbles in the rhythm of the heart, tiny variations in the time between beats. Curiously, this is a good indicator of neurological relaxation or arousal, messy and complex but reliable. For this test, HRV was measured in twenty-five scuba divers were tested in head-out immersion and while diving in a pool (27˚C). They found that “all HRV measures showed an increase in the parasympathetic activity” (relaxation) and “immersion under pool conditions is a powerful stimulus for both the sympathetic and parasympathetic nervous system.” Fascinating!
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
BACKGROUND: Heart rate variability (HRV) describes the cyclic variations in heart rate and offers a non-invasive tool for investigating the modulatory effects of neural mechanisms elicited by the autonomic nervous system on intrinsic heart rate.
OBJECTIVE: To introduce the HRV concept to healthy volunteers under control conditions and during scuba diving. In contrast with more established manoeuvres, diving probably activates both the sympathetic and parasympathetic nervous system through various stimuli-for example, through cardiac stretch receptors, respiration pattern, psychological stress, and diving reflex. A further aim of the study was to introduce a measure for determining a candidate's ability to scuba dive by providing (a) standard values for HRV measures (three from the time domain and three from the frequency domain) and (b) physiological responses to a strenuous manoeuvre such as scuba diving.
METHODS: Twenty five trained scuba divers were investigated while diving under pool conditions (27 degrees C) after the effects of head out immersion and submersion on HRV had been studied.
RESULTS AND CONCLUSIONS: (a) Immersion under pool conditions is a powerful stimulus for both the sympathetic and parasympathetic nervous system. (b) As neither the heart rate nor the HRV changed on going from immersion to submersion, the parasympathetic activation was probably due to haemodynamic alterations. (c) All HRV measures showed an increase in the parasympathetic activity. (d) If a physiological HRV is a mechanism for providing adaptability and flexibility, diving should not provoke circulatory problems in healthy subjects. (e) Either a lower than normal HRV under control conditions or a reduction in HRV induced by diving would be unphysiological, and a scuba diving candidate showing such characteristics should be further investigated.
- “Maximum and Resting Heart Rate in Treadmill and Deep-Water Running in Male International Volleyball Players,” A Cuesta-Vargas, JC Garcia-Romero, and R Kuisma, International Journal of Aquatic Research and Education, 2009.
- “Exercise rehabilitation restores physiological cardiovascular responses to short-term head-out water immersion in patients with chronic heart failure,” Laurent Mourot, D Teffaha, M Bouhaddi, F Ounissi, P Vernochet, B Dugue, J Regnard, and C Monpère, J Cardiopulm Rehabil Prev, 2010.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
- Relationships Between Sleep Quality and Pain-Related Factors for People with Chronic Low Back Pain: Tests of Reciprocal and Time of Day Effects. Gerhart 2017 Ann Behav Med.
- Modulation in the elastic properties of gastrocnemius muscle heads in individuals with plantar fasciitis and its relationship with pain. Zhou 2020 Sci Rep.
- Association Between Plantar Fasciitis and Isolated Gastrocnemius Tightness. Nakale 2018 Foot Ankle Int.
- No Added Benefit of Combining Dry Needling With Guideline-Based Physical Therapy When Managing Chronic Neck Pain: A Randomized Controlled Trial. Stieven 2020 J Orthop Sports Phys Ther.
- Effectiveness of customised foot orthoses for Achilles tendinopathy: a randomised controlled trial. Munteanu 2015 Br J Sports Med.